[Commits] Rev 3377: The main patch for the MWL#248 back-ported from in file:///home/igor/maria/maria-5.3-mwl248/

Igor Babaev igor at askmonty.org
Thu Jan 5 03:51:54 EET 2012


At file:///home/igor/maria/maria-5.3-mwl248/

------------------------------------------------------------
revno: 3377
revision-id: igor at askmonty.org-20120105015153-nmgz9hog9nwi060p
parent: igor at askmonty.org-20120103040636-nc6o55vsxqadd1n0
committer: Igor Babaev <igor at askmonty.org>
branch nick: maria-5.3-mwl248
timestamp: Wed 2012-01-04 17:51:53 -0800
message:
  The main patch for the MWL#248 back-ported from 
  lp:~igorb-seattle/mysql-server/mysql-azalea-wl4777.
-------------- next part --------------
=== modified file 'libmysqld/Makefile.am'
--- a/libmysqld/Makefile.am	2011-12-11 09:34:44 +0000
+++ b/libmysqld/Makefile.am	2012-01-05 01:51:53 +0000
@@ -75,6 +75,7 @@
 	sql_update.cc sql_yacc.cc table.cc thr_malloc.cc time.cc \
 	unireg.cc uniques.cc sql_union.cc hash_filo.cc \
 	spatial.cc gstream.cc sql_help.cc tztime.cc sql_cursor.cc \
+        sql_statistics.cc \
 	sp_head.cc sp_pcontext.cc sp.cc sp_cache.cc sp_rcontext.cc \
 	parse_file.cc sql_view.cc sql_trigger.cc my_decimal.cc \
 	rpl_filter.cc sql_partition.cc sql_builtin.cc sql_plugin.cc \

=== modified file 'mysql-test/include/system_db_struct.inc'
--- a/mysql-test/include/system_db_struct.inc	2006-12-11 16:44:03 +0000
+++ b/mysql-test/include/system_db_struct.inc	2012-01-05 01:51:53 +0000
@@ -16,3 +16,6 @@
 show create table event;
 show create table general_log;
 show create table slow_log;
+show create table table_stat;
+show create table column_stat;
+show create table index_stat;

=== added file 'mysql-test/include/world_schema_utf8.inc'
--- a/mysql-test/include/world_schema_utf8.inc	1970-01-01 00:00:00 +0000
+++ b/mysql-test/include/world_schema_utf8.inc	2012-01-05 01:51:53 +0000
@@ -0,0 +1,25 @@
+CREATE TABLE Country (
+  Code char(3) NOT NULL default '',
+  Name char(52) NOT NULL default '',
+  SurfaceArea float(10,2) NOT NULL default '0.00',
+  Population int(11) NOT NULL default '0',
+  Capital int(11) default NULL,
+  PRIMARY KEY  (Code),
+  UNIQUE INDEX (Name)
+) CHARACTER SET utf8 COLLATE utf8_bin;
+CREATE TABLE City (
+  ID int(11) NOT NULL auto_increment,
+  Name char(35) NOT NULL default '',
+  Country char(3) NOT NULL default '',
+  Population int(11) NOT NULL default '0',
+  PRIMARY KEY  (ID),
+  INDEX (Population),
+  INDEX (Country) 
+) CHARACTER SET utf8 COLLATE utf8_bin;
+CREATE TABLE CountryLanguage (
+  Country char(3) NOT NULL default '',
+  Language char(30) NOT NULL default '',
+  Percentage float(3,1) NOT NULL default '0.0',
+  PRIMARY KEY  (Country, Language),
+  INDEX (Percentage)
+) CHARACTER SET utf8 COLLATE utf8_bin;

=== modified file 'mysql-test/r/1st.result'
--- a/mysql-test/r/1st.result	2008-04-02 08:06:36 +0000
+++ b/mysql-test/r/1st.result	2012-01-05 01:51:53 +0000
@@ -6,6 +6,7 @@
 test
 show tables in mysql;
 Tables_in_mysql
+column_stat
 columns_priv
 db
 event
@@ -16,12 +17,14 @@
 help_relation
 help_topic
 host
+index_stat
 ndb_binlog_index
 plugin
 proc
 procs_priv
 servers
 slow_log
+table_stat
 tables_priv
 time_zone
 time_zone_leap_second

=== modified file 'mysql-test/r/connect.result'
--- a/mysql-test/r/connect.result	2011-02-28 17:39:30 +0000
+++ b/mysql-test/r/connect.result	2012-01-05 01:51:53 +0000
@@ -1,6 +1,7 @@
 drop table if exists t1,t2;
 show tables;
 Tables_in_mysql
+column_stat
 columns_priv
 db
 event
@@ -11,12 +12,14 @@
 help_relation
 help_topic
 host
+index_stat
 ndb_binlog_index
 plugin
 proc
 procs_priv
 servers
 slow_log
+table_stat
 tables_priv
 time_zone
 time_zone_leap_second
@@ -34,6 +37,7 @@
 grant ALL on *.* to test at 127.0.0.1 identified by "gambling";
 show tables;
 Tables_in_mysql
+column_stat
 columns_priv
 db
 event
@@ -44,12 +48,14 @@
 help_relation
 help_topic
 host
+index_stat
 ndb_binlog_index
 plugin
 proc
 procs_priv
 servers
 slow_log
+table_stat
 tables_priv
 time_zone
 time_zone_leap_second
@@ -75,6 +81,7 @@
 set password=old_password('gambling3');
 show tables;
 Tables_in_mysql
+column_stat
 columns_priv
 db
 event
@@ -85,12 +92,14 @@
 help_relation
 help_topic
 host
+index_stat
 ndb_binlog_index
 plugin
 proc
 procs_priv
 servers
 slow_log
+table_stat
 tables_priv
 time_zone
 time_zone_leap_second

=== modified file 'mysql-test/r/information_schema.result'
--- a/mysql-test/r/information_schema.result	2011-11-26 22:23:00 +0000
+++ b/mysql-test/r/information_schema.result	2012-01-05 01:51:53 +0000
@@ -95,6 +95,7 @@
 VIEWS
 XTRADB_ADMIN_COMMAND
 XTRADB_ENHANCEMENTS
+column_stat
 columns_priv
 db
 event
@@ -105,6 +106,7 @@
 help_relation
 help_topic
 host
+index_stat
 plugin
 proc
 procs_priv
@@ -115,6 +117,7 @@
 t3
 t4
 t5
+table_stat
 tables_priv
 time_zone
 time_zone_leap_second
@@ -132,6 +135,7 @@
 TABLE_PRIVILEGES	TABLE_PRIVILEGES
 TABLE_STATISTICS	TABLE_STATISTICS
 TRIGGERS	TRIGGERS
+table_stat	table_stat
 tables_priv	tables_priv
 time_zone	time_zone
 time_zone_leap_second	time_zone_leap_second
@@ -152,6 +156,7 @@
 TABLE_PRIVILEGES	TABLE_PRIVILEGES
 TABLE_STATISTICS	TABLE_STATISTICS
 TRIGGERS	TRIGGERS
+table_stat	table_stat
 tables_priv	tables_priv
 time_zone	time_zone
 time_zone_leap_second	time_zone_leap_second
@@ -172,6 +177,7 @@
 TABLE_PRIVILEGES	TABLE_PRIVILEGES
 TABLE_STATISTICS	TABLE_STATISTICS
 TRIGGERS	TRIGGERS
+table_stat	table_stat
 tables_priv	tables_priv
 time_zone	time_zone
 time_zone_leap_second	time_zone_leap_second

=== modified file 'mysql-test/r/information_schema_all_engines.result'
--- a/mysql-test/r/information_schema_all_engines.result	2010-09-11 18:43:48 +0000
+++ b/mysql-test/r/information_schema_all_engines.result	2012-01-05 01:51:53 +0000
@@ -382,4 +382,4 @@
 SELECT table_schema, count(*) FROM information_schema.TABLES WHERE table_schema IN ('mysql', 'INFORMATION_SCHEMA', 'test', 'mysqltest') AND table_name<>'ndb_binlog_index' AND table_name<>'ndb_apply_status' GROUP BY TABLE_SCHEMA;
 table_schema	count(*)
 information_schema	52
-mysql	22
+mysql	25

=== modified file 'mysql-test/r/log_tables_upgrade.result'
--- a/mysql-test/r/log_tables_upgrade.result	2010-09-05 23:15:34 +0000
+++ b/mysql-test/r/log_tables_upgrade.result	2012-01-05 01:51:53 +0000
@@ -19,6 +19,7 @@
 mtr.global_suppressions                            OK
 mtr.test_suppressions                              OK
 mysql
+mysql.column_stat                                  OK
 mysql.columns_priv                                 OK
 mysql.db                                           OK
 mysql.event                                        OK
@@ -28,12 +29,14 @@
 mysql.help_relation                                OK
 mysql.help_topic                                   OK
 mysql.host                                         OK
+mysql.index_stat                                   OK
 mysql.ndb_binlog_index                             OK
 mysql.plugin                                       OK
 mysql.proc                                         OK
 mysql.procs_priv                                   OK
 mysql.renamed_general_log                          OK
 mysql.servers                                      OK
+mysql.table_stat                                   OK
 mysql.tables_priv                                  OK
 mysql.time_zone                                    OK
 mysql.time_zone_leap_second                        OK

=== modified file 'mysql-test/r/mysqlcheck.result'
--- a/mysql-test/r/mysqlcheck.result	2011-01-29 17:51:12 +0000
+++ b/mysql-test/r/mysqlcheck.result	2012-01-05 01:51:53 +0000
@@ -3,6 +3,7 @@
 drop database if exists client_test_db;
 mtr.global_suppressions                            OK
 mtr.test_suppressions                              OK
+mysql.column_stat                                  OK
 mysql.columns_priv                                 OK
 mysql.db                                           OK
 mysql.event                                        OK
@@ -12,11 +13,13 @@
 mysql.help_relation                                OK
 mysql.help_topic                                   OK
 mysql.host                                         OK
+mysql.index_stat                                   OK
 mysql.ndb_binlog_index                             OK
 mysql.plugin                                       OK
 mysql.proc                                         OK
 mysql.procs_priv                                   OK
 mysql.servers                                      OK
+mysql.table_stat                                   OK
 mysql.tables_priv                                  OK
 mysql.time_zone                                    OK
 mysql.time_zone_leap_second                        OK
@@ -24,6 +27,7 @@
 mysql.time_zone_transition                         OK
 mysql.time_zone_transition_type                    OK
 mysql.user                                         OK
+mysql.column_stat                                  OK
 mysql.columns_priv                                 OK
 mysql.db                                           OK
 mysql.event                                        OK
@@ -33,11 +37,13 @@
 mysql.help_relation                                OK
 mysql.help_topic                                   OK
 mysql.host                                         OK
+mysql.index_stat                                   OK
 mysql.ndb_binlog_index                             OK
 mysql.plugin                                       OK
 mysql.proc                                         OK
 mysql.procs_priv                                   OK
 mysql.servers                                      OK
+mysql.table_stat                                   OK
 mysql.tables_priv                                  OK
 mysql.time_zone                                    OK
 mysql.time_zone_leap_second                        OK

=== added file 'mysql-test/r/statistics.result'
--- a/mysql-test/r/statistics.result	1970-01-01 00:00:00 +0000
+++ b/mysql-test/r/statistics.result	2012-01-05 01:51:53 +0000
@@ -0,0 +1,455 @@
+drop table if exists t1,t2;
+CREATE VIEW table_stat AS
+SELECT * FROM mysql.table_stat;
+CREATE VIEW column_stat AS
+SELECT db_name, table_name, column_name,
+min_value, max_value,
+CAST(nulls_ratio AS decimal(12,4)) AS 'nulls_ratio',
+CAST(avg_length AS decimal(12,4)) AS 'avg_length',
+CAST(avg_frequency AS decimal(12,4)) AS 'avg_frequency'
+    FROM mysql.column_stat;
+CREATE VIEW index_stat AS
+SELECT db_name, table_name, index_name, prefix_arity,
+CAST(avg_frequency AS decimal(12,4)) AS 'avg_frequency'
+    FROM mysql.index_stat;
+DELETE FROM mysql.table_stat;
+DELETE FROM mysql.column_stat;
+DELETE FROM mysql.index_stat;
+set optimizer_use_stat_tables='preferably';
+CREATE TABLE t1 (
+a int NOT NULL PRIMARY KEY,
+b varchar(32),
+c char(16),
+d date,
+e double,
+f bit(3),
+INDEX idx1 (b, e), 
+INDEX idx2(c, d),
+INDEX idx3 (d),
+INDEX idx4 (e, b, d)
+);
+INSERT INTO t1 VALUES
+(0, NULL, NULL, NULL, NULL, NULL),
+(7, 'xxxxxxxxxxxxxxxxxxxxxxxxxx', 'dddddddd', '1990-05-15', 0.1, b'100'),
+(17, 'vvvvvvvvvvvvv', 'aaaa', '1989-03-12', 0.01, b'101'),
+(1, 'vvvvvvvvvvvvv', NULL, '1989-03-12', 0.01, b'100'),
+(12, 'wwwwwwwwwwwwwwwwwwwwwwwwwwww', 'dddddddd', '1999-07-23', 0.112, b'001'),
+(23, 'vvvvvvvvvvvvv', 'dddddddd', '1999-07-23', 0.1, b'100'),
+(8, 'vvvvvvvvvvvvv', 'aaaa', '1999-07-23', 0.1, b'100'),
+(22, 'xxxxxxxxxxxxxxxxxxxxxxxxxx', 'aaaa', '1989-03-12', 0.112, b'001'),
+(31, 'wwwwwwwwwwwwwwwwwwwwwwwwwwww', 'aaaa', '1999-07-23', 0.01, b'001'),
+(10, NULL, 'aaaa', NULL, 0.01, b'010'),
+(5, 'wwwwwwwwwwwwwwwwwwwwwwwwwwww', 'dddddddd', '1999-07-23', 0.1, b'100'),
+(15, 'vvvvvvvvvvvvv', 'ccccccccc', '1990-05-15', 0.1, b'010'),
+(30, NULL, 'bbbbbb', NULL, NULL, b'100'),
+(38, 'zzzzzzzzzzzzzzzzzz', 'bbbbbb', NULL, NULL, NULL),
+(18, 'zzzzzzzzzzzzzzzzzz', 'ccccccccc', '1990-05-15', 0.01, b'010'),
+(9, 'yyy', 'bbbbbb', '1998-08-28', 0.01, NULL),
+(29, 'vvvvvvvvvvvvv', 'dddddddd', '1999-07-23', 0.012, b'010'),
+(3, 'yyy', 'dddddddd',  '1990-05-15', 0.112, b'010'),
+(39, 'zzzzzzzzzzzzzzzzzz', 'bbbbbb', NULL, 0.01, b'100'),
+(14, 'xxxxxxxxxxxxxxxxxxxxxxxxxx', 'ccccccccc', '1990-05-15', 0.1, b'100'),
+(40, 'zzzzzzzzzzzzzzzzzz', 'bbbbbb', '1989-03-12', NULL, NULL),
+(44, NULL, 'aaaa', '1989-03-12', NULL, b'010'),
+(19, 'vvvvvvvvvvvvv', 'ccccccccc', '1990-05-15', 0.012, b'011'),
+(21, 'zzzzzzzzzzzzzzzzzz', 'dddddddd', '1989-03-12', 0.112, b'100'),
+(45, NULL, NULL, '1989-03-12', NULL, b'011'),
+(2, 'wwwwwwwwwwwwwwwwwwwwwwwwwwww', 'ccccccccc', '1990-05-15', 0.1, b'001'),
+(35, 'yyy', 'aaaa', '1990-05-15', 0.05, b'011'),
+(4, 'vvvvvvvvvvvvv', 'dddddddd', '1999-07-23', 0.01, b'101'),
+(47, NULL, 'aaaa', '1990-05-15', 0.05, b'010'),
+(42, NULL, 'ccccccccc', '1989-03-12', 0.01, b'010'),
+(32, NULL, 'bbbbbb', '1990-05-15', 0.01, b'011'),
+(49, 'wwwwwwwwwwwwwwwwwwwwwwwwwwww' , 'aaaa', '1990-05-15', NULL, NULL),
+(43, 'wwwwwwwwwwwwwwwwwwwwwwwwwwww' , 'bbbbbb', '1990-05-15', NULL, b'100'),
+(37, 'yyy', NULL, '1989-03-12', 0.05, b'011'),
+(41, 'xxxxxxxxxxxxxxxxxxxxxxxxxx', 'ccccccccc', '1990-05-15', 0.05, NULL),
+(34, 'yyy', NULL, NULL, NULL, NULL),
+(33, 'zzzzzzzzzzzzzzzzzz', 'dddddddd', '1989-03-12', 0.05, b'011'),
+(24,  'wwwwwwwwwwwwwwwwwwwwwwwwwwww', 'dddddddd', '1990-05-15', 0.01,  b'101'),
+(11, 'yyy', 'ccccccccc', '1999-07-23', 0.1, NULL),
+(25, 'zzzzzzzzzzzzzzzzzz', 'bbb', '1989-03-12', 0.01,  b'101');
+ANALYZE TABLE t1;
+Table	Op	Msg_type	Msg_text
+test.t1	analyze	status	OK
+SELECT * FROM table_stat;
+db_name	table_name	cardinality
+test	t1	40
+SELECT * FROM column_stat;
+db_name	table_name	column_name	min_value	max_value	nulls_ratio	avg_length	avg_frequency
+test	t1	a	0	49	0.0000	4.0000	1.0000
+test	t1	b	vvvvvvvvvvvvv	zzzzzzzzzzzzzzzzzz	0.2000	17.1250	6.4000
+test	t1	c	aaaa	dddddddd	0.1250	6.6571	7.0000
+test	t1	d	1989-03-12	1999-07-23	0.1500	3.0000	8.5000
+test	t1	e	0.01	0.112	0.2250	8.0000	6.2000
+test	t1	f	1	5	0.2000	1.0000	6.4000
+SELECT * FROM index_stat;
+db_name	table_name	index_name	prefix_arity	avg_frequency
+test	t1	PRIMARY	1	1.0000
+test	t1	idx1	1	6.4000
+test	t1	idx1	2	1.6875
+test	t1	idx2	1	7.0000
+test	t1	idx2	2	2.3846
+test	t1	idx3	1	8.5000
+test	t1	idx4	1	6.2000
+test	t1	idx4	2	1.6875
+test	t1	idx4	3	1.1304
+SELECT COUNT(*) FROM t1;
+COUNT(*)
+40
+SELECT * FROM column_stat
+WHERE db_name='test' AND table_name='t1' AND column_name='a';
+db_name	table_name	column_name	min_value	max_value	nulls_ratio	avg_length	avg_frequency
+test	t1	a	0	49	0.0000	4.0000	1.0000
+SELECT MIN(t1.a), MAX(t1.a), 
+(SELECT COUNT(*) FROM t1 WHERE t1.b IS NULL) /
+(SELECT COUNT(*) FROM t1) AS "NULLS_RATIO(t1.a)",
+(SELECT COUNT(t1.a) FROM t1) /
+(SELECT COUNT(DISTINCT t1.a) FROM t1) AS "AVG_FREQUENCY(t1.a)"
+FROM t1;
+MIN(t1.a)	MAX(t1.a)	NULLS_RATIO(t1.a)	AVG_FREQUENCY(t1.a)
+0	49	0.2000	1.0000
+SELECT * FROM column_stat
+WHERE db_name='test' AND table_name='t1' AND column_name='b';
+db_name	table_name	column_name	min_value	max_value	nulls_ratio	avg_length	avg_frequency
+test	t1	b	vvvvvvvvvvvvv	zzzzzzzzzzzzzzzzzz	0.2000	17.1250	6.4000
+SELECT MIN(t1.b), MAX(t1.b), 
+(SELECT COUNT(*) FROM t1 WHERE t1.b IS NULL) /
+(SELECT COUNT(*) FROM t1) AS "NULLS_RATIO(t1.b)",
+(SELECT COUNT(t1.b) FROM t1) /
+(SELECT COUNT(DISTINCT t1.b) FROM t1) AS "AVG_FREQUENCY(t1.b)"
+FROM t1;
+MIN(t1.b)	MAX(t1.b)	NULLS_RATIO(t1.b)	AVG_FREQUENCY(t1.b)
+vvvvvvvvvvvvv	zzzzzzzzzzzzzzzzzz	0.2000	6.4000
+SELECT * FROM column_stat 
+WHERE db_name='test' AND table_name='t1' AND column_name='c';
+db_name	table_name	column_name	min_value	max_value	nulls_ratio	avg_length	avg_frequency
+test	t1	c	aaaa	dddddddd	0.1250	6.6571	7.0000
+SELECT MIN(t1.c), MAX(t1.c), 
+(SELECT COUNT(*) FROM t1 WHERE t1.c IS NULL) /
+(SELECT COUNT(*) FROM t1) AS "NULLS_RATIO(t1.c)",
+(SELECT COUNT(t1.c) FROM t1) /
+(SELECT COUNT(DISTINCT t1.c) FROM t1) AS "AVG_FREQUENCY(t1.c)"
+FROM t1;
+MIN(t1.c)	MAX(t1.c)	NULLS_RATIO(t1.c)	AVG_FREQUENCY(t1.c)
+aaaa	dddddddd	0.1250	7.0000
+SELECT * FROM column_stat
+WHERE db_name='test' AND table_name='t1' AND column_name='d';
+db_name	table_name	column_name	min_value	max_value	nulls_ratio	avg_length	avg_frequency
+test	t1	d	1989-03-12	1999-07-23	0.1500	3.0000	8.5000
+SELECT MIN(t1.d), MAX(t1.d), 
+(SELECT COUNT(*) FROM t1 WHERE t1.d IS NULL) /
+(SELECT COUNT(*) FROM t1) AS "NULLS_RATIO(t1.d)",
+(SELECT COUNT(t1.d) FROM t1) /
+(SELECT COUNT(DISTINCT t1.d) FROM t1) AS "AVG_FREQUENCY(t1.d)"
+FROM t1;
+MIN(t1.d)	MAX(t1.d)	NULLS_RATIO(t1.d)	AVG_FREQUENCY(t1.d)
+1989-03-12	1999-07-23	0.1500	8.5000
+SELECT * FROM column_stat
+WHERE db_name='test' AND table_name='t1' AND column_name='e';
+db_name	table_name	column_name	min_value	max_value	nulls_ratio	avg_length	avg_frequency
+test	t1	e	0.01	0.112	0.2250	8.0000	6.2000
+SELECT MIN(t1.e), MAX(t1.e), 
+(SELECT COUNT(*) FROM t1 WHERE t1.e IS NULL) /
+(SELECT COUNT(*) FROM t1) AS "NULLS_RATIO(t1.e)",
+(SELECT COUNT(t1.e) FROM t1) /
+(SELECT COUNT(DISTINCT t1.e) FROM t1) AS "AVG_FREQUENCY(t1.e)"
+FROM t1;
+MIN(t1.e)	MAX(t1.e)	NULLS_RATIO(t1.e)	AVG_FREQUENCY(t1.e)
+0.01	0.112	0.2250	6.2000
+SELECT * FROM index_stat
+WHERE db_name='test' AND table_name='t1' AND index_name='idx1';
+db_name	table_name	index_name	prefix_arity	avg_frequency
+test	t1	idx1	1	6.4000
+test	t1	idx1	2	1.6875
+SELECT 
+(SELECT COUNT(*) FROM t1 WHERE t1.b IS NOT NULL) /
+(SELECT COUNT(DISTINCT t1.b) FROM t1 WHERE t1.b IS NOT NULL)
+AS 'ARITY 1',
+(SELECT COUNT(*) FROM t1 WHERE t1.b IS NOT NULL AND t1.e IS NOT NULL) /
+(SELECT COUNT(DISTINCT t1.b, t1.e) FROM t1
+WHERE t1.b IS NOT NULL AND t1.e IS NOT NULL) 
+AS 'ARITY 2';
+ARITY 1	ARITY 2
+6.4000	1.6875
+SELECT * FROM index_stat
+WHERE db_name='test' AND table_name='t1' AND index_name='idx2';
+db_name	table_name	index_name	prefix_arity	avg_frequency
+test	t1	idx2	1	7.0000
+test	t1	idx2	2	2.3846
+SELECT 
+(SELECT COUNT(*) FROM t1 WHERE t1.c IS NOT NULL) /
+(SELECT COUNT(DISTINCT t1.c) FROM t1 WHERE t1.c IS NOT NULL) 
+AS 'ARITY 1',
+(SELECT COUNT(*) FROM t1 WHERE t1.c IS NOT NULL AND t1.d IS NOT NULL) /
+(SELECT COUNT(DISTINCT t1.c, t1.d) FROM t1
+WHERE t1.c IS NOT NULL AND t1.d IS NOT NULL)
+AS 'ARITY 2';
+ARITY 1	ARITY 2
+7.0000	2.3846
+SELECT * FROM index_stat
+WHERE db_name='test' AND table_name='t1' AND index_name='idx3';
+db_name	table_name	index_name	prefix_arity	avg_frequency
+test	t1	idx3	1	8.5000
+SELECT 
+(SELECT COUNT(*) FROM t1 WHERE t1.d IS NOT NULL) /
+(SELECT COUNT(DISTINCT t1.d) FROM t1 WHERE t1.d IS NOT NULL)
+AS 'ARITY 1';
+ARITY 1
+8.5000
+SELECT * FROM index_stat
+WHERE db_name='test' AND table_name='t1' AND index_name='idx4';
+db_name	table_name	index_name	prefix_arity	avg_frequency
+test	t1	idx4	1	6.2000
+test	t1	idx4	2	1.6875
+test	t1	idx4	3	1.1304
+SELECT 
+(SELECT COUNT(*) FROM t1 WHERE t1.e IS NOT NULL) /
+(SELECT COUNT(DISTINCT t1.e) FROM t1 WHERE t1.e IS NOT NULL)
+AS 'ARITY 1',
+(SELECT COUNT(*) FROM t1 WHERE t1.e IS NOT NULL AND t1.b IS NOT NULL) /
+(SELECT COUNT(DISTINCT t1.e, t1.b) FROM t1
+WHERE t1.e IS NOT NULL AND t1.b IS NOT NULL)
+AS 'ARITY 2',
+(SELECT COUNT(*) FROM t1
+WHERE t1.e IS NOT NULL AND t1.b IS NOT NULL AND t1.d IS NOT NULL) /  
+(SELECT COUNT(DISTINCT t1.e, t1.b, t1.d) FROM t1
+WHERE t1.e IS NOT NULL AND t1.b IS NOT NULL AND t1.d IS NOT NULL)
+AS 'ARITY 3';
+ARITY 1	ARITY 2	ARITY 3
+6.2000	1.6875	1.1304
+CREATE TABLE t2 LIKE t1;
+ALTER TABLE t2 ENGINE=InnoDB;
+INSERT INTO t2 SELECT * FROM t1;
+ANALYZE TABLE t2;
+Table	Op	Msg_type	Msg_text
+test.t2	analyze	status	OK
+SELECT * FROM table_stat;
+db_name	table_name	cardinality
+test	t1	40
+test	t2	40
+SELECT * FROM column_stat ORDER BY column_name;
+db_name	table_name	column_name	min_value	max_value	nulls_ratio	avg_length	avg_frequency
+test	t1	a	0	49	0.0000	4.0000	1.0000
+test	t2	a	0	49	0.0000	4.0000	1.0000
+test	t1	b	vvvvvvvvvvvvv	zzzzzzzzzzzzzzzzzz	0.2000	17.1250	6.4000
+test	t2	b	vvvvvvvvvvvvv	zzzzzzzzzzzzzzzzzz	0.2000	17.1250	6.4000
+test	t1	c	aaaa	dddddddd	0.1250	6.6571	7.0000
+test	t2	c	aaaa	dddddddd	0.1250	6.6571	7.0000
+test	t1	d	1989-03-12	1999-07-23	0.1500	3.0000	8.5000
+test	t2	d	1989-03-12	1999-07-23	0.1500	3.0000	8.5000
+test	t1	e	0.01	0.112	0.2250	8.0000	6.2000
+test	t2	e	0.01	0.112	0.2250	8.0000	6.2000
+test	t1	f	1	5	0.2000	1.0000	6.4000
+test	t2	f	1	5	0.2000	1.0000	6.4000
+SELECT * FROM index_stat ORDER BY index_name, prefix_arity, table_name;
+db_name	table_name	index_name	prefix_arity	avg_frequency
+test	t1	PRIMARY	1	1.0000
+test	t2	PRIMARY	1	1.0000
+test	t1	idx1	1	6.4000
+test	t2	idx1	1	6.4000
+test	t1	idx1	2	1.6875
+test	t2	idx1	2	1.6875
+test	t1	idx2	1	7.0000
+test	t2	idx2	1	7.0000
+test	t1	idx2	2	2.3846
+test	t2	idx2	2	2.3846
+test	t1	idx3	1	8.5000
+test	t2	idx3	1	8.5000
+test	t1	idx4	1	6.2000
+test	t2	idx4	1	6.2000
+test	t1	idx4	2	1.6875
+test	t2	idx4	2	1.6875
+test	t1	idx4	3	1.1304
+test	t2	idx4	3	1.1304
+DELETE FROM mysql.table_stat;
+DELETE FROM mysql.column_stat;
+DELETE FROM mysql.index_stat;
+ALTER TABLE t1
+DROP INDEX idx1,
+DROP INDEX idx4;
+ALTER TABLE t1
+MODIFY COLUMN b text,
+ADD INDEX idx1 (b(4), e), 
+ADD INDEX idx4 (e, b(4), d);
+ANALYZE TABLE t1;
+Table	Op	Msg_type	Msg_text
+test.t1	analyze	status	OK
+SELECT * FROM column_stat;
+db_name	table_name	column_name	min_value	max_value	nulls_ratio	avg_length	avg_frequency
+test	t1	a	0	49	0.0000	4.0000	1.0000
+test	t1	b	NULL	NULL	0.2000	17.1250	NULL
+test	t1	c	aaaa	dddddddd	0.1250	6.6571	7.0000
+test	t1	d	1989-03-12	1999-07-23	0.1500	3.0000	8.5000
+test	t1	e	0.01	0.112	0.2250	8.0000	6.2000
+test	t1	f	1	5	0.2000	1.0000	6.4000
+SELECT * FROM index_stat;
+db_name	table_name	index_name	prefix_arity	avg_frequency
+test	t1	PRIMARY	1	1.0000
+test	t1	idx2	1	7.0000
+test	t1	idx2	2	2.3846
+test	t1	idx3	1	8.5000
+test	t1	idx1	1	NULL
+test	t1	idx1	2	NULL
+test	t1	idx4	1	6.2000
+test	t1	idx4	2	NULL
+test	t1	idx4	3	NULL
+DROP TABLE t1,t2;
+DELETE FROM mysql.table_stat;
+DELETE FROM mysql.column_stat;
+DELETE FROM mysql.index_stat;
+set optimizer_use_stat_tables='never';
+set names utf8;
+CREATE DATABASE world;
+use world;
+CREATE TABLE Country (
+Code char(3) NOT NULL default '',
+Name char(52) NOT NULL default '',
+SurfaceArea float(10,2) NOT NULL default '0.00',
+Population int(11) NOT NULL default '0',
+Capital int(11) default NULL,
+PRIMARY KEY  (Code),
+UNIQUE INDEX (Name)
+) CHARACTER SET utf8 COLLATE utf8_bin;
+CREATE TABLE City (
+ID int(11) NOT NULL auto_increment,
+Name char(35) NOT NULL default '',
+Country char(3) NOT NULL default '',
+Population int(11) NOT NULL default '0',
+PRIMARY KEY  (ID),
+INDEX (Population),
+INDEX (Country) 
+) CHARACTER SET utf8 COLLATE utf8_bin;
+CREATE TABLE CountryLanguage (
+Country char(3) NOT NULL default '',
+Language char(30) NOT NULL default '',
+Percentage float(3,1) NOT NULL default '0.0',
+PRIMARY KEY  (Country, Language),
+INDEX (Percentage)
+) CHARACTER SET utf8 COLLATE utf8_bin;
+set optimizer_use_stat_tables='preferably';
+ANALYZE TABLE Country, City, CountryLanguage;
+SELECT * FROM test.table_stat;
+db_name	table_name	cardinality
+world	Country	239
+world	City	4079
+world	CountryLanguage	984
+SELECT * FROM test.column_stat;
+db_name	table_name	column_name	min_value	max_value	nulls_ratio	avg_length	avg_frequency
+world	Country	Code	ABW	ZWE	0.0000	3.0000	1.0000
+world	Country	Name	Afghanistan	Zimbabwe	0.0000	10.1088	1.0000
+world	Country	SurfaceArea	0.40	17075400.00	0.0000	4.0000	1.0042
+world	Country	Population	0	1277558000	0.0000	4.0000	1.0575
+world	Country	Capital	1	4074	0.0293	4.0000	1.0000
+world	City	ID	1	4079	0.0000	4.0000	1.0000
+world	City	Name	A Coru??a (La Coru??a)	??rgenc	0.0000	8.6416	1.0195
+world	City	Country	ABW	ZWE	0.0000	3.0000	17.5819
+world	City	Population	42	10500000	0.0000	4.0000	1.0467
+world	CountryLanguage	Country	ABW	ZWE	0.0000	3.0000	4.2232
+world	CountryLanguage	Language	Abhyasi	[South]Mande	0.0000	7.1778	2.1532
+world	CountryLanguage	Percentage	0.0	99.9	0.0000	4.0000	2.7640
+SELECT * FROM test.index_stat;
+db_name	table_name	index_name	prefix_arity	avg_frequency
+world	Country	PRIMARY	1	1.0000
+world	Country	Name	1	1.0000
+world	City	PRIMARY	1	1.0000
+world	City	Population	1	1.0467
+world	City	Country	1	17.5819
+world	CountryLanguage	PRIMARY	1	4.2232
+world	CountryLanguage	PRIMARY	2	1.0000
+world	CountryLanguage	Percentage	1	2.7640
+use test;
+set optimizer_use_stat_tables='never';
+CREATE DATABASE world_innodb;
+use world_innodb;
+CREATE TABLE Country (
+Code char(3) NOT NULL default '',
+Name char(52) NOT NULL default '',
+SurfaceArea float(10,2) NOT NULL default '0.00',
+Population int(11) NOT NULL default '0',
+Capital int(11) default NULL,
+PRIMARY KEY  (Code),
+UNIQUE INDEX (Name)
+) CHARACTER SET utf8 COLLATE utf8_bin;
+CREATE TABLE City (
+ID int(11) NOT NULL auto_increment,
+Name char(35) NOT NULL default '',
+Country char(3) NOT NULL default '',
+Population int(11) NOT NULL default '0',
+PRIMARY KEY  (ID),
+INDEX (Population),
+INDEX (Country) 
+) CHARACTER SET utf8 COLLATE utf8_bin;
+CREATE TABLE CountryLanguage (
+Country char(3) NOT NULL default '',
+Language char(30) NOT NULL default '',
+Percentage float(3,1) NOT NULL default '0.0',
+PRIMARY KEY  (Country, Language),
+INDEX (Percentage)
+) CHARACTER SET utf8 COLLATE utf8_bin;
+ALTER TABLE Country ENGINE=InnoDB;
+ALTER TABLE City ENGINE=InnoDB;
+ALTER TABLE CountryLanguage ENGINE=InnoDB;
+set optimizer_use_stat_tables='preferably';
+ANALYZE TABLE Country, City, CountryLanguage;
+SELECT * FROM test.table_stat;
+db_name	table_name	cardinality
+world	Country	239
+world	City	4079
+world	CountryLanguage	984
+world_innodb	Country	239
+world_innodb	City	4079
+world_innodb	CountryLanguage	984
+SELECT * FROM test.column_stat;
+db_name	table_name	column_name	min_value	max_value	nulls_ratio	avg_length	avg_frequency
+world	Country	Code	ABW	ZWE	0.0000	3.0000	1.0000
+world	Country	Name	Afghanistan	Zimbabwe	0.0000	10.1088	1.0000
+world	Country	SurfaceArea	0.40	17075400.00	0.0000	4.0000	1.0042
+world	Country	Population	0	1277558000	0.0000	4.0000	1.0575
+world	Country	Capital	1	4074	0.0293	4.0000	1.0000
+world	City	ID	1	4079	0.0000	4.0000	1.0000
+world	City	Name	A Coru??a (La Coru??a)	??rgenc	0.0000	8.6416	1.0195
+world	City	Country	ABW	ZWE	0.0000	3.0000	17.5819
+world	City	Population	42	10500000	0.0000	4.0000	1.0467
+world	CountryLanguage	Country	ABW	ZWE	0.0000	3.0000	4.2232
+world	CountryLanguage	Language	Abhyasi	[South]Mande	0.0000	7.1778	2.1532
+world	CountryLanguage	Percentage	0.0	99.9	0.0000	4.0000	2.7640
+world_innodb	Country	Code	ABW	ZWE	0.0000	3.0000	1.0000
+world_innodb	Country	Name	Afghanistan	Zimbabwe	0.0000	10.1088	1.0000
+world_innodb	Country	SurfaceArea	0.40	17075400.00	0.0000	4.0000	1.0042
+world_innodb	Country	Population	0	1277558000	0.0000	4.0000	1.0575
+world_innodb	Country	Capital	1	4074	0.0293	4.0000	1.0000
+world_innodb	City	ID	1	4079	0.0000	4.0000	1.0000
+world_innodb	City	Name	A Coru??a (La Coru??a)	??rgenc	0.0000	8.6416	1.0195
+world_innodb	City	Country	ABW	ZWE	0.0000	3.0000	17.5819
+world_innodb	City	Population	42	10500000	0.0000	4.0000	1.0467
+world_innodb	CountryLanguage	Country	ABW	ZWE	0.0000	3.0000	4.2232
+world_innodb	CountryLanguage	Language	Abhyasi	[South]Mande	0.0000	7.1778	2.1532
+world_innodb	CountryLanguage	Percentage	0.0	99.9	0.0000	4.0000	2.7640
+SELECT * FROM test.index_stat;
+db_name	table_name	index_name	prefix_arity	avg_frequency
+world	Country	PRIMARY	1	1.0000
+world	Country	Name	1	1.0000
+world	City	PRIMARY	1	1.0000
+world	City	Population	1	1.0467
+world	City	Country	1	17.5819
+world	CountryLanguage	PRIMARY	1	4.2232
+world	CountryLanguage	PRIMARY	2	1.0000
+world	CountryLanguage	Percentage	1	2.7640
+world_innodb	Country	PRIMARY	1	1.0000
+world_innodb	Country	Name	1	1.0000
+world_innodb	City	PRIMARY	1	1.0000
+world_innodb	City	Population	1	1.0467
+world_innodb	City	Country	1	17.5819
+world_innodb	CountryLanguage	PRIMARY	1	4.2232
+world_innodb	CountryLanguage	PRIMARY	2	1.0000
+world_innodb	CountryLanguage	Percentage	1	2.7640
+use test;
+DROP DATABASE world;
+DROP DATABASE world_innodb;
+DELETE FROM mysql.table_stat;
+DELETE FROM mysql.column_stat;
+DELETE FROM mysql.index_stat;
+DROP VIEW test.table_stat;
+DROP VIEW test.column_stat;
+DROP VIEW test.index_stat;

=== modified file 'mysql-test/r/system_mysql_db.result'
--- a/mysql-test/r/system_mysql_db.result	2011-09-26 17:26:47 +0000
+++ b/mysql-test/r/system_mysql_db.result	2012-01-05 01:51:53 +0000
@@ -1,5 +1,6 @@
 show tables;
 Tables_in_db
+column_stat
 columns_priv
 db
 event
@@ -10,12 +11,14 @@
 help_relation
 help_topic
 host
+index_stat
 ndb_binlog_index
 plugin
 proc
 procs_priv
 servers
 slow_log
+table_stat
 tables_priv
 time_zone
 time_zone_leap_second
@@ -262,5 +265,36 @@
   `server_id` int(10) unsigned NOT NULL,
   `sql_text` mediumtext NOT NULL
 ) ENGINE=CSV DEFAULT CHARSET=utf8 COMMENT='Slow log'
+show create table table_stat;
+Table	Create Table
+table_stat	CREATE TABLE `table_stat` (
+  `db_name` varchar(64) COLLATE utf8_bin NOT NULL,
+  `table_name` varchar(64) COLLATE utf8_bin NOT NULL,
+  `cardinality` bigint(21) unsigned DEFAULT NULL,
+  PRIMARY KEY (`db_name`,`table_name`)
+) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_bin COMMENT='Statistics on Tables'
+show create table column_stat;
+Table	Create Table
+column_stat	CREATE TABLE `column_stat` (
+  `db_name` varchar(64) COLLATE utf8_bin NOT NULL,
+  `table_name` varchar(64) COLLATE utf8_bin NOT NULL,
+  `column_name` varchar(64) COLLATE utf8_bin NOT NULL,
+  `min_value` varchar(255) COLLATE utf8_bin DEFAULT NULL,
+  `max_value` varchar(255) COLLATE utf8_bin DEFAULT NULL,
+  `nulls_ratio` double DEFAULT NULL,
+  `avg_length` double DEFAULT NULL,
+  `avg_frequency` double DEFAULT NULL,
+  PRIMARY KEY (`db_name`,`table_name`,`column_name`)
+) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_bin COMMENT='Statistics on Columns'
+show create table index_stat;
+Table	Create Table
+index_stat	CREATE TABLE `index_stat` (
+  `db_name` varchar(64) COLLATE utf8_bin NOT NULL,
+  `table_name` varchar(64) COLLATE utf8_bin NOT NULL,
+  `index_name` varchar(64) COLLATE utf8_bin NOT NULL,
+  `prefix_arity` int(11) unsigned NOT NULL,
+  `avg_frequency` double DEFAULT NULL,
+  PRIMARY KEY (`db_name`,`table_name`,`index_name`,`prefix_arity`)
+) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_bin COMMENT='Statistics on Indexes'
 show tables;
 Tables_in_test

=== modified file 'mysql-test/suite/pbxt/r/connect.result'
--- a/mysql-test/suite/pbxt/r/connect.result	2009-10-07 16:56:11 +0000
+++ b/mysql-test/suite/pbxt/r/connect.result	2012-01-05 01:51:53 +0000
@@ -1,6 +1,7 @@
 drop table if exists t1,t2;
 show tables;
 Tables_in_mysql
+column_stat
 columns_priv
 db
 event
@@ -11,12 +12,14 @@
 help_relation
 help_topic
 host
+index_stat
 ndb_binlog_index
 plugin
 proc
 procs_priv
 servers
 slow_log
+table_stat
 tables_priv
 time_zone
 time_zone_leap_second
@@ -34,6 +37,7 @@
 grant ALL on *.* to test at 127.0.0.1 identified by "gambling";
 show tables;
 Tables_in_mysql
+column_stat
 columns_priv
 db
 event
@@ -44,12 +48,14 @@
 help_relation
 help_topic
 host
+index_stat
 ndb_binlog_index
 plugin
 proc
 procs_priv
 servers
 slow_log
+table_stat
 tables_priv
 time_zone
 time_zone_leap_second
@@ -75,6 +81,7 @@
 set password=old_password('gambling3');
 show tables;
 Tables_in_mysql
+column_stat
 columns_priv
 db
 event
@@ -85,12 +92,14 @@
 help_relation
 help_topic
 host
+index_stat
 ndb_binlog_index
 plugin
 proc
 procs_priv
 servers
 slow_log
+table_stat
 tables_priv
 time_zone
 time_zone_leap_second

=== added file 'mysql-test/t/statistics.test'
--- a/mysql-test/t/statistics.test	1970-01-01 00:00:00 +0000
+++ b/mysql-test/t/statistics.test	2012-01-05 01:51:53 +0000
@@ -0,0 +1,290 @@
+--source include/have_innodb.inc
+--disable_warnings
+drop table if exists t1,t2;
+--enable_warnings
+
+CREATE VIEW table_stat AS
+SELECT * FROM mysql.table_stat;
+ 
+CREATE VIEW column_stat AS
+  SELECT db_name, table_name, column_name,
+         min_value, max_value,
+         CAST(nulls_ratio AS decimal(12,4)) AS 'nulls_ratio',
+         CAST(avg_length AS decimal(12,4)) AS 'avg_length',
+         CAST(avg_frequency AS decimal(12,4)) AS 'avg_frequency'
+    FROM mysql.column_stat;
+
+CREATE VIEW index_stat AS
+  SELECT db_name, table_name, index_name, prefix_arity,
+         CAST(avg_frequency AS decimal(12,4)) AS 'avg_frequency'
+    FROM mysql.index_stat;
+
+DELETE FROM mysql.table_stat;
+DELETE FROM mysql.column_stat;
+DELETE FROM mysql.index_stat;  
+   
+set optimizer_use_stat_tables='preferably';
+
+CREATE TABLE t1 (
+  a int NOT NULL PRIMARY KEY,
+  b varchar(32),
+  c char(16),
+  d date,
+  e double,
+  f bit(3),
+  INDEX idx1 (b, e), 
+  INDEX idx2(c, d),
+  INDEX idx3 (d),
+  INDEX idx4 (e, b, d)
+);
+
+INSERT INTO t1 VALUES
+  (0, NULL, NULL, NULL, NULL, NULL),
+  (7, 'xxxxxxxxxxxxxxxxxxxxxxxxxx', 'dddddddd', '1990-05-15', 0.1, b'100'),
+  (17, 'vvvvvvvvvvvvv', 'aaaa', '1989-03-12', 0.01, b'101'),
+  (1, 'vvvvvvvvvvvvv', NULL, '1989-03-12', 0.01, b'100'),
+  (12, 'wwwwwwwwwwwwwwwwwwwwwwwwwwww', 'dddddddd', '1999-07-23', 0.112, b'001'),
+  (23, 'vvvvvvvvvvvvv', 'dddddddd', '1999-07-23', 0.1, b'100'),
+  (8, 'vvvvvvvvvvvvv', 'aaaa', '1999-07-23', 0.1, b'100'),
+  (22, 'xxxxxxxxxxxxxxxxxxxxxxxxxx', 'aaaa', '1989-03-12', 0.112, b'001'),
+  (31, 'wwwwwwwwwwwwwwwwwwwwwwwwwwww', 'aaaa', '1999-07-23', 0.01, b'001'),
+  (10, NULL, 'aaaa', NULL, 0.01, b'010'),
+  (5, 'wwwwwwwwwwwwwwwwwwwwwwwwwwww', 'dddddddd', '1999-07-23', 0.1, b'100'),
+  (15, 'vvvvvvvvvvvvv', 'ccccccccc', '1990-05-15', 0.1, b'010'),
+  (30, NULL, 'bbbbbb', NULL, NULL, b'100'),
+  (38, 'zzzzzzzzzzzzzzzzzz', 'bbbbbb', NULL, NULL, NULL),
+  (18, 'zzzzzzzzzzzzzzzzzz', 'ccccccccc', '1990-05-15', 0.01, b'010'),
+  (9, 'yyy', 'bbbbbb', '1998-08-28', 0.01, NULL),
+  (29, 'vvvvvvvvvvvvv', 'dddddddd', '1999-07-23', 0.012, b'010'),
+  (3, 'yyy', 'dddddddd',  '1990-05-15', 0.112, b'010'),
+  (39, 'zzzzzzzzzzzzzzzzzz', 'bbbbbb', NULL, 0.01, b'100'),
+  (14, 'xxxxxxxxxxxxxxxxxxxxxxxxxx', 'ccccccccc', '1990-05-15', 0.1, b'100'),
+  (40, 'zzzzzzzzzzzzzzzzzz', 'bbbbbb', '1989-03-12', NULL, NULL),
+  (44, NULL, 'aaaa', '1989-03-12', NULL, b'010'),
+  (19, 'vvvvvvvvvvvvv', 'ccccccccc', '1990-05-15', 0.012, b'011'),
+  (21, 'zzzzzzzzzzzzzzzzzz', 'dddddddd', '1989-03-12', 0.112, b'100'),
+  (45, NULL, NULL, '1989-03-12', NULL, b'011'),
+  (2, 'wwwwwwwwwwwwwwwwwwwwwwwwwwww', 'ccccccccc', '1990-05-15', 0.1, b'001'),
+  (35, 'yyy', 'aaaa', '1990-05-15', 0.05, b'011'),
+  (4, 'vvvvvvvvvvvvv', 'dddddddd', '1999-07-23', 0.01, b'101'),
+  (47, NULL, 'aaaa', '1990-05-15', 0.05, b'010'),
+  (42, NULL, 'ccccccccc', '1989-03-12', 0.01, b'010'),
+  (32, NULL, 'bbbbbb', '1990-05-15', 0.01, b'011'),
+  (49, 'wwwwwwwwwwwwwwwwwwwwwwwwwwww' , 'aaaa', '1990-05-15', NULL, NULL),
+  (43, 'wwwwwwwwwwwwwwwwwwwwwwwwwwww' , 'bbbbbb', '1990-05-15', NULL, b'100'),
+  (37, 'yyy', NULL, '1989-03-12', 0.05, b'011'),
+  (41, 'xxxxxxxxxxxxxxxxxxxxxxxxxx', 'ccccccccc', '1990-05-15', 0.05, NULL),
+  (34, 'yyy', NULL, NULL, NULL, NULL),
+  (33, 'zzzzzzzzzzzzzzzzzz', 'dddddddd', '1989-03-12', 0.05, b'011'),
+  (24,  'wwwwwwwwwwwwwwwwwwwwwwwwwwww', 'dddddddd', '1990-05-15', 0.01,  b'101'),
+  (11, 'yyy', 'ccccccccc', '1999-07-23', 0.1, NULL),
+  (25, 'zzzzzzzzzzzzzzzzzz', 'bbb', '1989-03-12', 0.01,  b'101');
+
+ANALYZE TABLE t1;
+
+SELECT * FROM table_stat;
+SELECT * FROM column_stat;
+SELECT * FROM index_stat;
+
+SELECT COUNT(*) FROM t1;
+
+SELECT * FROM column_stat
+  WHERE db_name='test' AND table_name='t1' AND column_name='a';
+SELECT MIN(t1.a), MAX(t1.a), 
+       (SELECT COUNT(*) FROM t1 WHERE t1.b IS NULL) /
+       (SELECT COUNT(*) FROM t1) AS "NULLS_RATIO(t1.a)",
+       (SELECT COUNT(t1.a) FROM t1) /
+       (SELECT COUNT(DISTINCT t1.a) FROM t1) AS "AVG_FREQUENCY(t1.a)"
+FROM t1;
+
+SELECT * FROM column_stat
+  WHERE db_name='test' AND table_name='t1' AND column_name='b';
+SELECT MIN(t1.b), MAX(t1.b), 
+       (SELECT COUNT(*) FROM t1 WHERE t1.b IS NULL) /
+       (SELECT COUNT(*) FROM t1) AS "NULLS_RATIO(t1.b)",
+       (SELECT COUNT(t1.b) FROM t1) /
+       (SELECT COUNT(DISTINCT t1.b) FROM t1) AS "AVG_FREQUENCY(t1.b)"
+FROM t1;
+
+SELECT * FROM column_stat 
+  WHERE db_name='test' AND table_name='t1' AND column_name='c';
+SELECT MIN(t1.c), MAX(t1.c), 
+       (SELECT COUNT(*) FROM t1 WHERE t1.c IS NULL) /
+       (SELECT COUNT(*) FROM t1) AS "NULLS_RATIO(t1.c)",
+       (SELECT COUNT(t1.c) FROM t1) /
+       (SELECT COUNT(DISTINCT t1.c) FROM t1) AS "AVG_FREQUENCY(t1.c)"
+FROM t1;
+
+SELECT * FROM column_stat
+  WHERE db_name='test' AND table_name='t1' AND column_name='d';
+SELECT MIN(t1.d), MAX(t1.d), 
+       (SELECT COUNT(*) FROM t1 WHERE t1.d IS NULL) /
+       (SELECT COUNT(*) FROM t1) AS "NULLS_RATIO(t1.d)",
+       (SELECT COUNT(t1.d) FROM t1) /
+       (SELECT COUNT(DISTINCT t1.d) FROM t1) AS "AVG_FREQUENCY(t1.d)"
+FROM t1;
+
+SELECT * FROM column_stat
+  WHERE db_name='test' AND table_name='t1' AND column_name='e';
+SELECT MIN(t1.e), MAX(t1.e), 
+       (SELECT COUNT(*) FROM t1 WHERE t1.e IS NULL) /
+       (SELECT COUNT(*) FROM t1) AS "NULLS_RATIO(t1.e)",
+       (SELECT COUNT(t1.e) FROM t1) /
+       (SELECT COUNT(DISTINCT t1.e) FROM t1) AS "AVG_FREQUENCY(t1.e)"
+FROM t1;
+
+SELECT * FROM index_stat
+  WHERE db_name='test' AND table_name='t1' AND index_name='idx1';
+SELECT 
+  (SELECT COUNT(*) FROM t1 WHERE t1.b IS NOT NULL) /
+  (SELECT COUNT(DISTINCT t1.b) FROM t1 WHERE t1.b IS NOT NULL)
+  AS 'ARITY 1',
+  (SELECT COUNT(*) FROM t1 WHERE t1.b IS NOT NULL AND t1.e IS NOT NULL) /
+  (SELECT COUNT(DISTINCT t1.b, t1.e) FROM t1
+     WHERE t1.b IS NOT NULL AND t1.e IS NOT NULL) 
+  AS 'ARITY 2';
+
+SELECT * FROM index_stat
+  WHERE db_name='test' AND table_name='t1' AND index_name='idx2';
+SELECT 
+  (SELECT COUNT(*) FROM t1 WHERE t1.c IS NOT NULL) /
+  (SELECT COUNT(DISTINCT t1.c) FROM t1 WHERE t1.c IS NOT NULL) 
+  AS 'ARITY 1',
+  (SELECT COUNT(*) FROM t1 WHERE t1.c IS NOT NULL AND t1.d IS NOT NULL) /
+  (SELECT COUNT(DISTINCT t1.c, t1.d) FROM t1
+     WHERE t1.c IS NOT NULL AND t1.d IS NOT NULL)
+  AS 'ARITY 2';
+
+SELECT * FROM index_stat
+  WHERE db_name='test' AND table_name='t1' AND index_name='idx3';
+SELECT 
+  (SELECT COUNT(*) FROM t1 WHERE t1.d IS NOT NULL) /
+  (SELECT COUNT(DISTINCT t1.d) FROM t1 WHERE t1.d IS NOT NULL)
+  AS 'ARITY 1';
+
+SELECT * FROM index_stat
+  WHERE db_name='test' AND table_name='t1' AND index_name='idx4';
+SELECT 
+  (SELECT COUNT(*) FROM t1 WHERE t1.e IS NOT NULL) /
+  (SELECT COUNT(DISTINCT t1.e) FROM t1 WHERE t1.e IS NOT NULL)
+  AS 'ARITY 1',
+  (SELECT COUNT(*) FROM t1 WHERE t1.e IS NOT NULL AND t1.b IS NOT NULL) /
+  (SELECT COUNT(DISTINCT t1.e, t1.b) FROM t1
+         WHERE t1.e IS NOT NULL AND t1.b IS NOT NULL)
+  AS 'ARITY 2',
+  (SELECT COUNT(*) FROM t1
+     WHERE t1.e IS NOT NULL AND t1.b IS NOT NULL AND t1.d IS NOT NULL) /  
+  (SELECT COUNT(DISTINCT t1.e, t1.b, t1.d) FROM t1
+     WHERE t1.e IS NOT NULL AND t1.b IS NOT NULL AND t1.d IS NOT NULL)
+  AS 'ARITY 3';
+
+
+CREATE TABLE t2 LIKE t1;
+ALTER TABLE t2 ENGINE=InnoDB;
+INSERT INTO t2 SELECT * FROM t1;
+
+ANALYZE TABLE t2;
+
+SELECT * FROM table_stat;
+SELECT * FROM column_stat ORDER BY column_name;
+SELECT * FROM index_stat ORDER BY index_name, prefix_arity, table_name;
+
+
+DELETE FROM mysql.table_stat;
+DELETE FROM mysql.column_stat;
+DELETE FROM mysql.index_stat;
+
+ALTER TABLE t1
+  DROP INDEX idx1,
+  DROP INDEX idx4;
+ALTER TABLE t1
+  MODIFY COLUMN b text,
+  ADD INDEX idx1 (b(4), e), 
+  ADD INDEX idx4 (e, b(4), d);
+  
+ANALYZE TABLE t1;
+
+SELECT * FROM column_stat;
+SELECT * FROM index_stat;
+
+DROP TABLE t1,t2;
+
+DELETE FROM mysql.table_stat;
+DELETE FROM mysql.column_stat;
+DELETE FROM mysql.index_stat;
+
+set optimizer_use_stat_tables='never';  
+
+set names utf8;
+
+CREATE DATABASE world;
+
+use world;
+
+--source include/world_schema_utf8.inc
+
+--disable_query_log
+--disable_result_log
+--disable_warnings
+--source include/world.inc
+--enable_warnings
+--enable_result_log
+--enable_query_log
+
+set optimizer_use_stat_tables='preferably';
+
+--disable_result_log
+ANALYZE TABLE Country, City, CountryLanguage;
+--enable_result_log
+
+SELECT * FROM test.table_stat;
+SELECT * FROM test.column_stat;
+SELECT * FROM test.index_stat;
+
+use test;
+
+set optimizer_use_stat_tables='never'; 
+
+CREATE DATABASE world_innodb;
+
+use world_innodb;
+
+--source include/world_schema_utf8.inc
+
+ALTER TABLE Country ENGINE=InnoDB;
+ALTER TABLE City ENGINE=InnoDB;
+ALTER TABLE CountryLanguage ENGINE=InnoDB;
+
+--disable_query_log
+--disable_result_log
+--disable_warnings
+--source include/world.inc
+--enable_warnings
+--enable_result_log
+--enable_query_log
+
+set optimizer_use_stat_tables='preferably';
+
+--disable_result_log
+ANALYZE TABLE Country, City, CountryLanguage;
+--enable_result_log
+
+SELECT * FROM test.table_stat;
+SELECT * FROM test.column_stat;
+SELECT * FROM test.index_stat;
+
+use test;
+
+DROP DATABASE world;
+DROP DATABASE world_innodb;
+
+DELETE FROM mysql.table_stat;
+DELETE FROM mysql.column_stat;
+DELETE FROM mysql.index_stat;
+  
+DROP VIEW test.table_stat;
+DROP VIEW test.column_stat;
+DROP VIEW test.index_stat;
+
+   
+    
\ No newline at end of file

=== modified file 'mysql-test/t/system_mysql_db_fix30020.test'
--- a/mysql-test/t/system_mysql_db_fix30020.test	2009-02-02 11:36:03 +0000
+++ b/mysql-test/t/system_mysql_db_fix30020.test	2012-01-05 01:51:53 +0000
@@ -97,7 +97,8 @@
 DROP TABLE db, host, user, func, plugin, tables_priv, columns_priv,
 procs_priv, servers, help_category, help_keyword, help_relation, help_topic, proc,
 time_zone, time_zone_leap_second, time_zone_name, time_zone_transition,
-time_zone_transition_type, general_log, slow_log, event, ndb_binlog_index;
+time_zone_transition_type, general_log, slow_log, event, ndb_binlog_index,
+table_stat, column_stat, index_stat;
 
 -- enable_query_log
 

=== modified file 'mysql-test/t/system_mysql_db_fix40123.test'
--- a/mysql-test/t/system_mysql_db_fix40123.test	2011-03-01 12:24:36 +0000
+++ b/mysql-test/t/system_mysql_db_fix40123.test	2012-01-05 01:51:53 +0000
@@ -59,6 +59,11 @@
 
 CREATE TABLE time_zone_leap_second (   Transition_time bigint signed NOT NULL,   Correction int signed NOT NULL,   PRIMARY KEY TranTime (Transition_time) ) engine=MyISAM CHARACTER SET utf8   comment='Leap seconds information for time zones';
 
+CREATE TABLE table_stat (db_name varchar(64) NOT NULL, table_name varchar(64) NOT NULL, cardinality bigint(21) unsigned DEFAULT NULL, PRIMARY KEY (db_name,table_name) ) ENGINE=MyISAM CHARACTER SET utf8 COLLATE utf8_bin comment='Statistics on Tables';
+
+CREATE TABLE column_stat (db_name varchar(64) NOT NULL, table_name varchar(64) NOT NULL, column_name varchar(64) NOT NULL, min_value varchar(255) DEFAULT NULL, max_value varchar(255) DEFAULT NULL, nulls_ratio double DEFAULT NULL, avg_length double DEFAULT NULL, avg_frequency double DEFAULT NULL, PRIMARY KEY (db_name,table_name,column_name) ) ENGINE=MyISAM CHARACTER SET utf8 COLLATE utf8_bin comment='Statistics on Columns';
+
+CREATE TABLE index_stat (db_name varchar(64) NOT NULL, table_name varchar(64) NOT NULL, index_name varchar(64) NOT NULL, prefix_arity int(11) unsigned NOT NULL, avg_frequency double DEFAULT NULL, PRIMARY KEY (db_name,table_name,index_name,prefix_arity) ) ENGINE=MyISAM CHARACTER SET utf8 COLLATE utf8_bin comment='Statistics on Indexes';
 
 # Run the mysql_fix_privilege_tables.sql using "mysql --force"
 --exec $MYSQL --force test < $MYSQL_FIX_PRIVILEGE_TABLES > $MYSQLTEST_VARDIR/log/system_mysql_db_fix40123.log 2>&1
@@ -72,7 +77,7 @@
 -- disable_query_log
 
 # Drop all tables created by this test
-DROP TABLE db, host, user, func, plugin, tables_priv, columns_priv, procs_priv, servers, help_category, help_keyword, help_relation, help_topic, proc, time_zone, time_zone_leap_second, time_zone_name, time_zone_transition, time_zone_transition_type, general_log, slow_log, event, ndb_binlog_index;
+DROP TABLE db, host, user, func, plugin, tables_priv, columns_priv, procs_priv, servers, help_category, help_keyword, help_relation, help_topic, proc, time_zone, time_zone_leap_second, time_zone_name, time_zone_transition, time_zone_transition_type, general_log, slow_log, event, ndb_binlog_index, table_stat, column_stat, index_stat;
 
 -- enable_query_log
 

=== modified file 'mysql-test/t/system_mysql_db_fix50030.test'
--- a/mysql-test/t/system_mysql_db_fix50030.test	2011-03-01 12:24:36 +0000
+++ b/mysql-test/t/system_mysql_db_fix50030.test	2012-01-05 01:51:53 +0000
@@ -66,6 +66,12 @@
 
 INSERT INTO servers VALUES ('test','localhost','test','root','', 0,'','mysql','root');
 
+CREATE TABLE table_stat (db_name varchar(64) NOT NULL, table_name varchar(64) NOT NULL, cardinality bigint(21) unsigned DEFAULT NULL, PRIMARY KEY (db_name,table_name) ) ENGINE=MyISAM CHARACTER SET utf8 COLLATE utf8_bin comment='Statistics on Tables';
+
+CREATE TABLE column_stat (db_name varchar(64) NOT NULL, table_name varchar(64) NOT NULL, column_name varchar(64) NOT NULL, min_value varchar(255) DEFAULT NULL, max_value varchar(255) DEFAULT NULL, nulls_ratio double DEFAULT NULL, avg_length double DEFAULT NULL, avg_frequency double DEFAULT NULL, PRIMARY KEY (db_name,table_name,column_name) ) ENGINE=MyISAM CHARACTER SET utf8 COLLATE utf8_bin comment='Statistics on Columns';
+
+CREATE TABLE index_stat (db_name varchar(64) NOT NULL, table_name varchar(64) NOT NULL, index_name varchar(64) NOT NULL, prefix_arity int(11) unsigned NOT NULL, avg_frequency double DEFAULT NULL, PRIMARY KEY (db_name,table_name,index_name,prefix_arity) ) ENGINE=MyISAM CHARACTER SET utf8 COLLATE utf8_bin comment='Statistics on Indexes';
+
 # Run the mysql_fix_privilege_tables.sql using "mysql --force"
 --exec $MYSQL --force test < $MYSQL_FIX_PRIVILEGE_TABLES > $MYSQLTEST_VARDIR/log/system_mysql_db_fix50030.log 2>&1
 
@@ -78,7 +84,7 @@
 -- disable_query_log
 
 # Drop all tables created by this test
-DROP TABLE db, host, user, func, plugin, tables_priv, columns_priv, procs_priv, servers, help_category, help_keyword, help_relation, help_topic, proc, time_zone, time_zone_leap_second, time_zone_name, time_zone_transition, time_zone_transition_type, general_log, slow_log, event, ndb_binlog_index;
+DROP TABLE db, host, user, func, plugin, tables_priv, columns_priv, procs_priv, servers, help_category, help_keyword, help_relation, help_topic, proc, time_zone, time_zone_leap_second, time_zone_name, time_zone_transition, time_zone_transition_type, general_log, slow_log, event, ndb_binlog_index, table_stat, column_stat, index_stat;
 
 -- enable_query_log
 

=== modified file 'mysql-test/t/system_mysql_db_fix50117.test'
--- a/mysql-test/t/system_mysql_db_fix50117.test	2011-03-01 12:24:36 +0000
+++ b/mysql-test/t/system_mysql_db_fix50117.test	2012-01-05 01:51:53 +0000
@@ -85,6 +85,12 @@
 
 CREATE TABLE IF NOT EXISTS ndb_binlog_index (Position BIGINT UNSIGNED NOT NULL, File VARCHAR(255) NOT NULL, epoch BIGINT UNSIGNED NOT NULL, inserts BIGINT UNSIGNED NOT NULL, updates BIGINT UNSIGNED NOT NULL, deletes BIGINT UNSIGNED NOT NULL, schemaops BIGINT UNSIGNED NOT NULL, PRIMARY KEY(epoch)) ENGINE=MYISAM;
 
+CREATE TABLE table_stat (db_name varchar(64) NOT NULL, table_name varchar(64) NOT NULL, cardinality bigint(21) unsigned DEFAULT NULL, PRIMARY KEY (db_name,table_name) ) ENGINE=MyISAM CHARACTER SET utf8 COLLATE utf8_bin comment='Statistics on Tables';
+
+CREATE TABLE column_stat (db_name varchar(64) NOT NULL, table_name varchar(64) NOT NULL, column_name varchar(64) NOT NULL, min_value varchar(255) DEFAULT NULL, max_value varchar(255) DEFAULT NULL, nulls_ratio double DEFAULT NULL, avg_length double DEFAULT NULL, avg_frequency double DEFAULT NULL, PRIMARY KEY (db_name,table_name,column_name) ) ENGINE=MyISAM CHARACTER SET utf8 COLLATE utf8_bin comment='Statistics on Columns';
+
+CREATE TABLE index_stat (db_name varchar(64) NOT NULL, table_name varchar(64) NOT NULL, index_name varchar(64) NOT NULL, prefix_arity int(11) unsigned NOT NULL, avg_frequency double DEFAULT NULL, PRIMARY KEY (db_name,table_name,index_name,prefix_arity) ) ENGINE=MyISAM CHARACTER SET utf8 COLLATE utf8_bin comment='Statistics on Indexes';
+
 # Run the mysql_fix_privilege_tables.sql using "mysql --force"
 --exec $MYSQL --force test < $MYSQL_FIX_PRIVILEGE_TABLES > $MYSQLTEST_VARDIR/log/system_mysql_db_fix50117.log 2>&1
 
@@ -97,7 +103,7 @@
 -- disable_query_log
 
 # Drop all tables created by this test
-DROP TABLE db, host, user, func, plugin, tables_priv, columns_priv, procs_priv, servers, help_category, help_keyword, help_relation, help_topic, proc, time_zone, time_zone_leap_second, time_zone_name, time_zone_transition, time_zone_transition_type, general_log, slow_log, event, ndb_binlog_index;
+DROP TABLE db, host, user, func, plugin, tables_priv, columns_priv, procs_priv, servers, help_category, help_keyword, help_relation, help_topic, proc, time_zone, time_zone_leap_second, time_zone_name, time_zone_transition, time_zone_transition_type, general_log, slow_log, event, ndb_binlog_index, table_stat, column_stat, index_stat;
 
 -- enable_query_log
 

=== modified file 'scripts/mysql_system_tables.sql'
--- a/scripts/mysql_system_tables.sql	2011-12-11 09:34:44 +0000
+++ b/scripts/mysql_system_tables.sql	2012-01-05 01:51:53 +0000
@@ -102,3 +102,8 @@
 
 CREATE TABLE IF NOT EXISTS ndb_binlog_index (Position BIGINT UNSIGNED NOT NULL, File VARCHAR(255) NOT NULL, epoch BIGINT UNSIGNED NOT NULL, inserts BIGINT UNSIGNED NOT NULL, updates BIGINT UNSIGNED NOT NULL, deletes BIGINT UNSIGNED NOT NULL, schemaops BIGINT UNSIGNED NOT NULL, PRIMARY KEY(epoch)) ENGINE=MYISAM;
 
+CREATE TABLE IF NOT EXISTS table_stat (db_name varchar(64) NOT NULL, table_name varchar(64) NOT NULL, cardinality bigint(21) unsigned DEFAULT NULL, PRIMARY KEY (db_name,table_name) ) ENGINE=MyISAM CHARACTER SET utf8 COLLATE utf8_bin comment='Statistics on Tables';
+
+CREATE TABLE IF NOT EXISTS column_stat (db_name varchar(64) NOT NULL, table_name varchar(64) NOT NULL, column_name varchar(64) NOT NULL, min_value varchar(255) DEFAULT NULL, max_value varchar(255) DEFAULT NULL, nulls_ratio double DEFAULT NULL, avg_length double DEFAULT NULL, avg_frequency double DEFAULT NULL, PRIMARY KEY (db_name,table_name,column_name) ) ENGINE=MyISAM CHARACTER SET utf8 COLLATE utf8_bin comment='Statistics on Columns';
+
+CREATE TABLE IF NOT EXISTS index_stat (db_name varchar(64) NOT NULL, table_name varchar(64) NOT NULL, index_name varchar(64) NOT NULL, prefix_arity int(11) unsigned NOT NULL, avg_frequency double DEFAULT NULL, PRIMARY KEY (db_name,table_name,index_name,prefix_arity) ) ENGINE=MyISAM CHARACTER SET utf8 COLLATE utf8_bin comment='Statistics on Indexes';

=== modified file 'sql/CMakeLists.txt'
--- a/sql/CMakeLists.txt	2011-12-12 12:00:33 +0000
+++ b/sql/CMakeLists.txt	2012-01-05 01:51:53 +0000
@@ -69,7 +69,8 @@
                sql_map.cc sql_parse.cc  sql_partition.cc sql_plugin.cc
                sql_prepare.cc sql_rename.cc 
                debug_sync.cc debug_sync.h
-               sql_repl.cc sql_select.cc sql_show.cc sql_state.c sql_string.cc 
+               sql_repl.cc sql_select.cc sql_show.cc sql_state.c
+               sql_statistics.cc sql_string.cc 
                sql_table.cc sql_test.cc sql_trigger.cc sql_udf.cc sql_union.cc
                sql_update.cc sql_view.cc strfunc.cc table.cc thr_malloc.cc 
                time.cc tztime.cc uniques.cc unireg.cc item_xmlfunc.cc 

=== modified file 'sql/Makefile.am'
--- a/sql/Makefile.am	2011-12-11 09:34:44 +0000
+++ b/sql/Makefile.am	2012-01-05 01:51:53 +0000
@@ -73,7 +73,7 @@
 			log_event_old.h rpl_record_old.h \
 			sql_sort.h sql_cache.h set_var.h \
 			spatial.h gstream.h client_settings.h tzfile.h \
-			tztime.h my_decimal.h\
+			tztime.h my_decimal.h sql_statistics.h \
 			sp_head.h sp_pcontext.h sp_rcontext.h sp.h sp_cache.h \
 			parse_file.h sql_view.h	sql_trigger.h \
 			sql_array.h sql_cursor.h events.h scheduler.h \
@@ -127,7 +127,7 @@
 			repl_failsafe.h repl_failsafe.cc \
 			sql_olap.cc sql_view.cc \
 			gstream.cc spatial.cc sql_help.cc sql_cursor.cc \
-			tztime.cc my_decimal.cc\
+                        tztime.cc my_decimal.cc sql_statistics.cc \
 			sp_head.cc sp_pcontext.cc  sp_rcontext.cc sp.cc \
 			sp_cache.cc parse_file.cc sql_trigger.cc \
                         event_scheduler.cc event_data_objects.cc \

=== modified file 'sql/field.cc'
--- a/sql/field.cc	2011-12-11 09:34:44 +0000
+++ b/sql/field.cc	2012-01-05 01:51:53 +0000
@@ -70,7 +70,7 @@
 ((ulong) ((LL(1) << min(arg, 4) * 8) - LL(1)))
 
 #define ASSERT_COLUMN_MARKED_FOR_READ DBUG_ASSERT(!table || (!table->read_set || bitmap_is_set(table->read_set, field_index)))
-#define ASSERT_COLUMN_MARKED_FOR_WRITE_OR_COMPUTED DBUG_ASSERT(!table || (!table->write_set || bitmap_is_set(table->write_set, field_index) || bitmap_is_set(table->vcol_set, field_index)))
+#define ASSERT_COLUMN_MARKED_FOR_WRITE_OR_COMPUTED DBUG_ASSERT(is_stat_field || !table || (!table->write_set || bitmap_is_set(table->write_set, field_index) || bitmap_is_set(table->vcol_set, field_index)))
 
 /*
   Rules for merging different types of fields in UNION
@@ -1330,7 +1330,8 @@
   flags=null_ptr ? 0: NOT_NULL_FLAG;
   comment.str= (char*) "";
   comment.length=0;
-  field_index= 0;
+  field_index= 0;   
+  is_stat_field= FALSE;
 }
 
 
@@ -1817,6 +1818,21 @@
 }
 
 
+
+Field *Field::clone(MEM_ROOT *root, TABLE *new_table, my_ptrdiff_t diff,
+                    bool stat_flag)
+{
+  Field *tmp;
+  if ((tmp= (Field*) memdup_root(root,(char*) this,size_of())))
+  {
+    tmp->init(new_table);
+    tmp->move_field_offset(diff);
+  }
+  tmp->is_stat_field= stat_flag;
+  return tmp;
+}
+
+
 /****************************************************************************
   Field_null, a field that always return NULL
 ****************************************************************************/

=== modified file 'sql/field.h'
--- a/sql/field.h	2011-12-11 09:34:44 +0000
+++ b/sql/field.h	2012-01-05 01:51:53 +0000
@@ -33,6 +33,7 @@
 class Protocol;
 class Create_field;
 class Relay_log_info;
+class Count_distinct_field;
 struct ha_field_option_struct;
 
 struct st_cache_field;
@@ -183,6 +184,57 @@
    */
   bool is_created_from_null_item;
 
+  bool is_stat_field; /* TRUE in Field objects created for column min/max values */
+
+  /* Statistical data on a column */
+  class Column_statistics
+  {
+  public:
+    /* 
+      Bitmap indicating  what statistical characteristics
+      are available for the column
+    */
+    uint32 column_stat_nulls;
+
+    /* Minimum value for the column */
+    Field *min_value; 
+    /* Maximum value for the column */   
+    Field *max_value;
+    /* 
+      The ratio Z/N, where N is the total number of rows,
+      Z is the number of nulls in the column
+    */
+    double nulls_ratio; 
+    /*
+      Average number of bytes occupied by the representation of a
+      value of the column in memory buffers such as join buffer.
+      CHAR values are stripped of trailing spaces.
+      Flexible values are stripped of their length prefixes.
+    */
+    double avg_length;
+    /*
+      The ratio N/D, where N is the number of rows with null value 
+      in the column, D the number of distinct values among them
+    */
+    double avg_frequency;
+  };
+  
+  /*
+    This structure is used for statistical data on the column
+    that has been read from the statistical table column_stat
+  */ 
+  Column_statistics read_stat;
+  /*
+    This structure is used for statistical data on the column that
+    is collected by the function collect_statistics_for_table
+  */
+  Column_statistics write_stat;
+
+  /* These members are used only when collecting statistics on the column */
+  ha_rows nulls;   
+  ulonglong column_total_length;
+  Count_distinct_field *count_distinct;
+
   /* 
     This is additional data provided for any computed(virtual) field.
     In particular it includes a pointer to the item by  which this field
@@ -284,6 +336,26 @@
   virtual uint32 data_length() { return pack_length(); }
   virtual uint32 sort_length() const { return pack_length(); }
 
+  /* 
+    Get the number bytes occupied by the value in the field.
+    CHAR values are stripped of trailing spaces.
+    Flexible values are stripped of their length.
+  */
+  virtual uint32 value_length()
+  {
+    uint len;
+    if (!zero_pack() &&
+	(type() == MYSQL_TYPE_STRING &&
+        (len= pack_length()) >= 4 && len < 256))
+    {
+      uchar *str, *end;
+      for (str= ptr, end= str+len; end > str && end[-1] == ' '; end--);
+      len=(uint) (end-str); 
+      return len;
+    } 
+    return data_length();
+  }
+
   /**
      Get the maximum size of the data in packed format.
 
@@ -325,6 +397,36 @@
   { return cmp(a, b); }
   virtual int key_cmp(const uchar *str, uint length)
   { return cmp(ptr,str); }
+  /*
+    Update the value m of the 'min_val' field with the current value v
+    of this field if force_update is set to TRUE or if v < m.
+    Return TRUE if the value has been updated.
+  */  
+  virtual bool update_min(Field *min_val, bool force_update)
+  { 
+    bool update_fl= force_update || cmp(ptr, min_val->ptr) < 0;
+    if (update_fl)
+    {
+      min_val->set_notnull();
+      memcpy(min_val->ptr, ptr, pack_length());
+    }
+    return update_fl;
+  }
+  /*
+    Update the value m of the 'max_val' field with the current value v
+    of this field if force_update is set to TRUE or if v > m.
+    Return TRUE if the value has been updated.
+  */  
+  virtual bool update_max(Field *max_val, bool force_update)
+  { 
+    bool update_fl= force_update || cmp(ptr, max_val->ptr) > 0;
+    if (update_fl)
+    {
+      max_val->set_notnull();
+      memcpy(max_val->ptr, ptr, pack_length());
+    }
+    return update_fl;
+  }
   virtual uint decimals() const { return 0; }
   /*
     Caller beware: sql_type can change str.Ptr, so check
@@ -396,6 +498,8 @@
                                uchar *new_ptr, uchar *new_null_ptr,
                                uint new_null_bit);
   Field *clone(MEM_ROOT *mem_root, struct st_table *new_table);
+  Field *clone(MEM_ROOT *mem_root, TABLE *new_table, my_ptrdiff_t diff,
+               bool stat_flag= FALSE);
   inline void move_field(uchar *ptr_arg,uchar *null_ptr_arg,uchar null_bit_arg)
   {
     ptr=ptr_arg; null_ptr=null_ptr_arg; null_bit=null_bit_arg;
@@ -1785,6 +1889,10 @@
   int cmp_binary(const uchar *a,const uchar *b, uint32 max_length=~0L);
   int key_cmp(const uchar *,const uchar*);
   int key_cmp(const uchar *str, uint length);
+  /* Never update the value of min_val for a blob field */
+  bool update_min(Field *min_val, bool force_update) { return FALSE; }
+  /* Never update the value of max_val for a blob field */
+  bool update_max(Field *max_val, bool force_update) { return FALSE; }
   uint32 key_length() const { return 0; }
   void sort_string(uchar *buff,uint length);
   uint32 pack_length() const
@@ -1802,6 +1910,7 @@
   { return (uint32) (packlength); }
   uint row_pack_length() { return pack_length_no_ptr(); }
   uint32 sort_length() const;
+  uint32 value_length() { return get_length(); }
   virtual uint32 max_data_length() const
   {
     return (uint32) (((ulonglong) 1 << (packlength*8)) -1);
@@ -2059,6 +2168,28 @@
   { return cmp_binary((uchar *) a, (uchar *) b); }
   int key_cmp(const uchar *str, uint length);
   int cmp_offset(uint row_offset);
+  bool update_min(Field *min_val, bool force_update)
+  { 
+    longlong val= val_int();
+    bool update_fl= force_update || val < min_val->val_int();
+    if (update_fl)
+    {
+      min_val->set_notnull();
+      min_val->store(val, FALSE);
+    }
+    return update_fl;
+  }
+  bool update_max(Field *max_val, bool force_update)
+  { 
+    longlong val= val_int();
+    bool update_fl= force_update || val > max_val->val_int();
+    if (update_fl)
+    {
+      max_val->set_notnull();
+      max_val->store(val, FALSE);
+    }
+    return update_fl;
+  }
   void get_image(uchar *buff, uint length, CHARSET_INFO *cs)
   { get_key_image(buff, length, itRAW); }   
   void set_image(const uchar *buff,uint length, CHARSET_INFO *cs)

=== modified file 'sql/item_sum.cc'
--- a/sql/item_sum.cc	2011-12-11 09:34:44 +0000
+++ b/sql/item_sum.cc	2012-01-05 01:51:53 +0000
@@ -887,14 +887,14 @@
 
 /* Declarations for auxilary C-callbacks */
 
-static int simple_raw_key_cmp(void* arg, const void* key1, const void* key2)
+int simple_raw_key_cmp(void* arg, const void* key1, const void* key2)
 {
     return memcmp(key1, key2, *(uint *) arg);
 }
 
 
-static int item_sum_distinct_walk(void *element, element_count num_of_dups,
-                                  void *item)
+int item_sum_distinct_walk(void *element, element_count num_of_dups,
+                           void *item)
 {
   return ((Item_sum_distinct*) (item))->unique_walk_function(element);
 }
@@ -2362,7 +2362,7 @@
 
 C_MODE_START
 
-static int count_distinct_walk(void *elem, element_count count, void *arg)
+int count_distinct_walk(void *elem, element_count count, void *arg)
 {
   (*((ulonglong*)arg))++;
   return 0;

=== modified file 'sql/mysql_priv.h'
--- a/sql/mysql_priv.h	2011-12-15 08:21:15 +0000
+++ b/sql/mysql_priv.h	2012-01-05 01:51:53 +0000
@@ -1519,6 +1519,12 @@
 int update_virtual_fields(THD *thd, TABLE *table, bool ignore_stored= FALSE);
 int dynamic_column_error_message(enum_dyncol_func_result rc);
 
+int read_statistics_for_table(THD *thd, TABLE *table);
+int collect_statistics_for_table(THD *thd, TABLE *table);
+int update_statistics_for_table(THD *thd, TABLE *table);
+
+extern TYPELIB optimizer_use_stat_tables_typelib;
+
 #endif /* MYSQL_SERVER */
 
 #ifdef HAVE_OPENSSL
@@ -1935,6 +1941,9 @@
 /* Functions to work with system tables. */
 bool open_system_tables_for_read(THD *thd, TABLE_LIST *table_list,
                                  Open_tables_state *backup);
+bool unlock_tables_n_open_system_tables_for_write(THD *thd,
+                                                  TABLE_LIST *table_list,
+                                                  Open_tables_state *backup);
 void close_system_tables(THD *thd, Open_tables_state *backup);
 TABLE *open_system_table_for_update(THD *thd, TABLE_LIST *one_table);
 
@@ -2589,6 +2598,13 @@
 		     LEX_STRING component);
 int get_var_with_binlog(THD *thd, enum_sql_command sql_command,
                         LEX_STRING &name, user_var_entry **out_entry);
+
+/* item_sum.cc */
+extern "C" int simple_raw_key_cmp(void* arg, const void* key1,
+                                  const void* key2);
+extern "C" int count_distinct_walk(void *elem, element_count count, void *arg);
+int simple_str_key_cmp(void* arg, uchar* key1, uchar* key2);
+
 /* log.cc */
 bool flush_error_log(void);
 

=== modified file 'sql/mysqld.cc'
--- a/sql/mysqld.cc	2011-12-15 22:26:59 +0000
+++ b/sql/mysqld.cc	2012-01-05 01:51:53 +0000
@@ -3759,6 +3759,8 @@
   global_system_variables.character_set_results= default_charset_info;
   global_system_variables.character_set_client= default_charset_info;
 
+  global_system_variables.optimizer_use_stat_tables= 0;
+ 
   if (!(character_set_filesystem=
         get_charset_by_csname(character_set_filesystem_name,
                               MY_CS_PRIMARY, MYF(MY_WME))))

=== modified file 'sql/set_var.cc'
--- a/sql/set_var.cc	2011-12-15 12:43:28 +0000
+++ b/sql/set_var.cc	2012-01-05 01:51:53 +0000
@@ -537,6 +537,12 @@
                                                          "progress_report_time",
                                                          &SV::progress_report_time);
 
+static sys_var_thd_enum         sys_optimizer_use_stat_tables(&vars, 
+                                               "optimizer_use_stat_tables",
+                                               &SV::optimizer_use_stat_tables,
+                                               &optimizer_use_stat_tables_typelib,
+                                               NULL);
+
 static sys_var_const            sys_pid_file(&vars, "pid_file",
                                              OPT_GLOBAL, SHOW_CHAR,
                                              (uchar*) pidfile_name);

=== modified file 'sql/sql_base.cc'
--- a/sql/sql_base.cc	2011-12-11 16:39:33 +0000
+++ b/sql/sql_base.cc	2012-01-05 01:51:53 +0000
@@ -4855,6 +4855,13 @@
         parent_l->next_global= *parent_l->table->child_last_l;
       }
 
+      if (thd->variables.optimizer_use_stat_tables > 0)
+      {
+        if (tables->table &&  tables->table->s && 
+            tables->table->s->table_category != TABLE_CATEGORY_SYSTEM)    
+	  (void) read_statistics_for_table(thd, tables->table);
+      }
+
       if (refresh)				// Refresh in progress
       {
         /*
@@ -9496,6 +9503,72 @@
 
 
 /*
+  Unlock opened tables and open and lock system tables for write.
+
+  SYNOPSIS
+    open_system_tables_for_read()
+      thd         Thread context.
+      table_list  List of tables to open.
+      backup      Pointer to Open_tables_state instance where
+                  information about currently open tables will be
+                  saved, and from which will be restored when we will
+                  end work with system tables.
+
+  DESCRIPTION
+    The function first unlocks the opened tables, but do not close them.
+    Then it opens and locks for write the specified system tables.
+  
+  NOTE
+    The system tables cannot be locked for write without unlocking
+    the current opened tables. Yet in some cases we still need valid TABLE
+    structures for these tables to be able to extract data that is to be
+    written into the system tables.
+    This function is used when updating the statistical tables. 
+
+  RETURN
+    FALSE   Success
+    TRUE    Error
+*/
+
+bool
+unlock_tables_n_open_system_tables_for_write(THD *thd,
+                                             TABLE_LIST *table_list,
+                                             Open_tables_state *backup)
+{
+  Query_tables_list query_tables_list_backup;
+  LEX *lex= thd->lex;
+
+  DBUG_ENTER("unlock_tables_n_open_system_tables_for_write");
+
+  mysql_unlock_tables(thd, thd->lock);
+  thd->lock= 0;
+
+  lex->reset_n_backup_query_tables_list(&query_tables_list_backup);
+  thd->reset_n_backup_open_tables_state(backup);
+
+  if (open_and_lock_tables_derived(thd, table_list, FALSE))
+  {
+    lex->restore_backup_query_tables_list(&query_tables_list_backup);
+    goto error;
+  }
+
+  for (TABLE_LIST *tables= table_list; tables; tables= tables->next_global)
+  {
+    DBUG_ASSERT(tables->table->s->table_category == TABLE_CATEGORY_SYSTEM);
+    tables->table->use_all_columns();
+  }
+  lex->restore_backup_query_tables_list(&query_tables_list_backup);
+
+  DBUG_RETURN(FALSE);
+
+error:
+  close_system_tables(thd, backup);
+
+  DBUG_RETURN(TRUE);
+}
+
+
+/*
   Close system tables, opened with open_system_tables_for_read().
 
   SYNOPSIS

=== modified file 'sql/sql_class.h'
--- a/sql/sql_class.h	2011-12-11 09:34:44 +0000
+++ b/sql/sql_class.h	2012-01-05 01:51:53 +0000
@@ -458,6 +458,7 @@
   ulong optimizer_search_depth;
   /* A bitmap for switching optimizations on/off */
   ulong optimizer_switch;
+  ulong optimizer_use_stat_tables;
   ulong preload_buff_size;
   ulong profiling_history_size;
   ulong query_cache_type;

=== added file 'sql/sql_statistics.cc'
--- a/sql/sql_statistics.cc	1970-01-01 00:00:00 +0000
+++ b/sql/sql_statistics.cc	2012-01-05 01:51:53 +0000
@@ -0,0 +1,1587 @@
+/* Copyright (C) 2009 MySQL AB
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; version 2 of the License.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
+
+/**
+  @file
+
+  @brief
+  functions to update persitent statistical tables and to read from them
+
+  @defgroup Query_Optimizer  Query Optimizer
+  @{
+*/
+
+#include "mysql_priv.h"
+#include "sql_statistics.h"
+
+/*
+  The system variable 'optimizer_use_stat_tables' can take one of the
+  following values:
+  "never", "complementary", "preferably", "exclusively". 
+  If the values of the variable 'optimizer_use_stat_tables' is set to
+  "never then any statistical data from  the persistent statistical tables
+  is ignored by the optimizer.
+  If the value of the variable 'optimizer_use_stat_tables' is set to
+  "complementary" then a particular statistical characteristic is used
+  by the optimizer only if the database engine does not provide similar
+  statistics. For example, 'nulls_ratio' for table columns  currently 
+  are not provided by any engine. So optimizer uses this statistical data
+  from the  statistical tables. At the same time it does not use 
+  'avg_frequency' for any index prefix from the statistical tables since
+  the a similar statistical characteristic 'records_per_key' can be
+  requested from the database engine.
+  If the value the variable 'optimizer_use_stat_tables' is set to
+  "preferably" the optimizer uses a particular statistical data only if
+  it can't be found in the statistical data.
+  If the value of the variable 'optimizer_use_stat_tables' is set to
+  "exclusively" the optimizer never uses statistical data that can be
+  returned by the database engine Only statistical data from the
+  statistical tables is used.
+  If an ANALYZE command is executed then it results in collecting
+  statistical data for the tables specified by the command and storing
+  the collected statistics in the persistent statistical tables only
+  when the value of the variable 'optimizer_use_stat_tables' is not
+  equal to "never".
+*/ 
+   
+const char *optimizer_use_stat_tables_modes[] =
+  {"never", "complentary", "preferably", "exclusively", NullS};
+
+TYPELIB optimizer_use_stat_tables_typelib= {
+  array_elements(optimizer_use_stat_tables_modes) - 1, "",
+  optimizer_use_stat_tables_modes, NULL
+};
+
+/* Currently there are only 3 persistent statistical tables */
+static const uint STATISTICS_TABLES= 3;
+
+/* 
+  The names of the statistical tables in this list must correspond the
+  definitions of the tables in the file ../scripts/mysql_system_tables.sql
+*/
+static const char *STAT_TABLE_NAME[STATISTICS_TABLES]=
+{
+  "table_stat",
+  "column_stat",
+  "index_stat"
+};
+
+/* 
+  @details
+  The function sets null bits stored in the bitmap table_field->write_stat
+  for all statistical values collected for a column.
+*/
+inline void set_nulls_for_write_column_stat_values(Field *table_field)
+{
+  table_field->write_stat.column_stat_nulls= 
+    ((1 << (COLUMN_STAT_AVG_FREQUENCY-COLUMN_STAT_COLUMN_NAME))-1) <<
+    (COLUMN_STAT_COLUMN_NAME+1);
+}
+
+/* 
+  @details
+  The function sets null bits stored in the bitmap table_field->read_stat
+  for all statistical values collected for a column.
+*/
+inline void set_nulls_for_read_column_stat_values(Field *table_field)
+{
+  table_field->read_stat.column_stat_nulls= 
+    ((1 << (COLUMN_STAT_AVG_FREQUENCY-COLUMN_STAT_COLUMN_NAME))-1) <<
+    (COLUMN_STAT_COLUMN_NAME+1);
+}
+
+/* 
+  @details
+  The function removes the null bit stored in the bitmap
+  table_field->write_stat for the statistical value collected
+  on the statistical column number stat_field_no.  
+*/
+inline void set_not_null_for_write_column_stat_value(Field *table_field,
+                                                     uint stat_field_no)
+{
+  table_field->write_stat.column_stat_nulls&= ~(1 << stat_field_no);
+}  
+  
+/* 
+  @details
+  The function removes the null bit stored in the bitmap
+  table_field->read_stat for the statistical value collected
+  on the statistical column number stat_field_no.  
+*/
+inline void set_not_null_for_read_column_stat_value(Field *table_field,
+                                                    uint stat_field_no)
+{
+  table_field->read_stat.column_stat_nulls&= ~(1 << stat_field_no);
+}
+
+/* 
+  @details
+  The function checks the null bit stored in the bitmap
+  table_field->read_stat for the statistical value collected
+  on the statistical column number stat_field_no.  
+*/
+inline bool check_null_for_write_column_stat_value(Field *table_field,
+                                                   uint stat_field_no)
+{
+  return table_field->write_stat.column_stat_nulls & (1 << stat_field_no);
+}
+
+/*
+  Stat_table is the base class for classes Table_stat, Column_stat and
+  Index_stat. The methods of these classes allow us table to read
+  statistical data from statistical tables and write collected statistical
+  data into statistical data. Objects of the classes Table_stat, Column_stat
+  and Index stat are used for reading/writing statistics from/into 
+  persistent tables table_stat, column_stat and index_stat correspondingly.
+  These tables are stored in the system database 'mysql'.
+
+  Statistics is read and written always for a given database table t. When
+  an  object of any of these classes is created a pointer to the TABLE
+  structure for this database table is passed as a parameter to the constructor
+  of the object. The other parameter is a pointer to the TABLE structure for
+  the corresponding statistical table st. So construction of an object to 
+  read/write statistical data on table t from/into statistical table st 
+  requires both table t and st to be opened.
+
+  Reading/writing statistical data from/into a statistical table is always
+  performed by key. At the moment there is only one key defined for each
+  statistical table and this key is primary.
+  The primary key for the table table_stat is built as (db_name, table_name).
+  The primary key for the table column_stat is built as (db_name, table_name,
+  column_name).
+  The primary key for the table index_stat is built as (db_name, table_name,
+  index_name, prefix_arity).
+
+  Reading statistical data from a statistical table is performed by the 
+  following pattern. First a table dependent method sets the values of the
+  the fields that comprise the lookup key. Then an implementation of the 
+  method get_stat_values() declared in Stat_table as a pure virtual method
+  finds the row from the statistical table by the set key. If the row is
+  found the values of statistical fields are read from this row and are
+  distributed in the internal structures.
+
+  Let's assume the statistical data is read for table t from database db.
+
+  When statistical data is searched in the table table_stat first 
+  Table_stat::set_key_fields() should set the fields of db_name and
+  table_name. Then get_stat_values looks for a row by the set key value,
+  and, if the row is found, reads the value from the column
+  table_stat.cardinality into the field read_stat.cardinality of the TABLE
+  structure for table t and sets the value of read_stat.cardinality_is_null
+  from this structure to FALSE. If the value of the 'cardinality' column
+  in the row is null or if no row is found read_stat.cardinality_is_null
+  is set to TRUE.
+
+  When statistical data is searched in the table column_stat first
+  Column_stat::set_key_fields() should set the fields of db_name, table_name
+  and column_name with column_name taken out of the only parameter f of the
+  Field* type passed to this method. After this get_stat_values looks
+  for a row by the set key value. If the row is found the values of statistical 
+  data columns min_value, max_value, nulls_ratio, avg_length, avg_frequency
+  are read into internal structures. Values of nulls_ratio, avg_length,
+  avg_frequency are read into the corresponding fields of the read_stat
+  structure from the Field object f, while values from min_value and max_value
+  are copied into the min_value and  max_value record buffers attached to the
+  TABLE structure for table t.
+  If the value of a statistical column in the found row is null, then the
+  corresponding flag in the f->read_stat.column_stat_nulls bitmap is set off.
+  Otherwise the flag is set on. If no row is found for the column the all flags
+  in f->column_stat_nulls are set off.
+  
+  When statistical data is searched in the table index_stat first
+  Index_stat::set_key_fields() has to be called to set the fields of db_name,
+  table_name, index_name and prefix_arity. The value of index_name is extracted
+  from the first parameter key_info of the KEY* type passed to the method.
+  This parameter  specifies the index of interest idx. The second parameter
+  passed to the method specifies the arity k of the index prefix for which
+  statistical data is to be read. E.g. if the index idx consists of 3
+  components (p1,p2,p3) the table  index_stat usually will contain 3 rows for
+  this index: the first - for the prefix (p1), the second - for the prefix
+  (p1,p2), and the third - for the the prefix (p1,p2,p3). After the key fields
+  has been set a call of get_stat_value looks for a row by the set key value.
+  If the row is found and the value of the avg_frequency column is not null 
+  then this value is assigned to key_info->read_stat.avg_frequency[k].
+  Otherwise 0 is assigned to this element. 
+
+  The method Stat_table::update_stat is used to write statistical data
+  collected in the internal structures into a statistical table st.
+  It is assumed that before any invocation of this method a call of the
+  function st.set_key_fields has set the values of the primary key fields
+  that serve to locate the row from the statistical table st where the 
+  the colected statistical data from internal structures are to be written
+  to. The statistical data is written from the counterparts of the
+  statistical fields of internal structures into which it would be read
+  by the functions get_stat_values. The counterpart fields are used
+  only when statistics is collected
+  When updating/inserting a row from the statistical table st the method
+  Stat_table::update_stat calls the implementation of the pure virtual
+  method store_field_values to transfer statistical data from the fields
+  of internal structures to the fields of record buffer used for updates
+  of the statistical table st.     
+*/  
+         
+class Stat_table 
+{
+private:
+  /* Handler used for the retrieval of the statistical table stat_table */
+  handler *stat_file;
+  
+  KEY *stat_key_info;   /* Structure for the index to access stat_table */
+  uint stat_key_length; /* Length of the key to access stat_table */   
+  uchar *record[2];     /* Record buffers used to access/update stat_table */
+  uint stat_key_idx;    /* The number of the key to access stat_table */
+
+protected:
+  /* Statistical table to read statistics from or to update */
+  TABLE *stat_table;
+  
+  /* Table for which statistical data is read / updated */
+  TABLE *table;     
+  char *db_name;        /* Name of the database containing 'table' */ 
+  uint db_name_len;     /* Length of db_name */
+  char *table_name;     /* Name of the table 'table' */
+  uint table_name_len;  /* Name of table_name */
+
+public:
+
+  /*
+    @details
+    This constructor has to be called by any constructor of the derived
+    classes. The constructor 'tunes' the private and protected members of
+    the constructed object to the statistical table 'stat_table' with the
+    statistical data of our interest and to the table 'tab' for which this
+    statistics has been collected.
+  */  
+  Stat_table(TABLE *stat, TABLE *tab) :stat_table(stat), table(tab)
+  {
+    stat_file= stat_table->file;
+    /* Currently any statistical table has only one key */
+    stat_key_idx= 0;
+    stat_key_info= &stat_table->key_info[stat_key_idx];
+    stat_key_length= stat_key_info->key_length;
+    record[0]= stat_table->record[0];
+    record[1]= stat_table->record[1];
+    db_name= table->s->db.str;
+    db_name_len= table->s->db.length;
+    table_name= table->s->table_name.str;
+    table_name_len= table->s->table_name.length;    
+  }
+
+  virtual ~Stat_table() {}
+
+  /*
+    @brief
+    Store statistical data into fields of the statistical table
+   
+    @details
+    This is a purely virtual method.
+    The implementation for any derived class shall put the appropriate
+    statistical data into the corresponding fields of stat_table.
+    
+    @note
+    The method is called by the update_stat function.
+  */      
+  virtual void store_stat_fields()= 0;
+
+  /*
+    @brief
+    Read statistical data from fields of the statistical table
+   
+    @details
+    This is a purely virtual method.
+    The implementation for any derived read shall read the appropriate
+    statistical data from the corresponding fields of stat_table.    
+  */      
+  virtual void get_stat_values()= 0;
+
+  /*
+    @breif
+    Find a record by key in the statistical table
+
+    @details
+    The function looks for a record in stat_table by its primary key.
+    It assumes that the key fields have been already stored in the record
+    buffer of stat_table.
+
+    @retval
+    FALSE    the record is not found
+    @retval
+    TRUE     the record is found
+  */
+  bool find_stat()
+  {
+    uchar key[MAX_KEY_LENGTH];
+    key_copy(key, record[0], stat_key_info, stat_key_length);
+    return !stat_file->ha_index_read_idx_map(record[0], stat_key_idx, key,
+                                             HA_WHOLE_KEY, HA_READ_KEY_EXACT);
+  }
+
+  /*
+    @breif
+    Update/insert a record in the statistical table with new statistics
+
+    @details
+    The function first looks for a record by its primary key in the statistical
+    table stat_table. If the record is found the function updates statistical
+    fields of the records. The data for these fields are taken from internal
+    structures containing info on the table 'table'. If the record is not
+    found the function inserts a new record with the primary key set to the
+    search key and the statistical data taken from the internal structures.
+    The function assumes that the key fields have been already stored in
+    the record buffer of stat_table.
+
+    @retval
+    FALSE    success with the update/insert of the record
+    @retval
+    TRUE     failure with the update/insert of the record
+
+    @note
+    The function calls the virtual method store_stat_fields to populate the
+    statistical fields of the updated/inserted row with new statistics.
+  */
+  bool update_stat()
+  {
+    int err;
+    if (find_stat())
+    {    
+      store_record(stat_table, record[1]);
+      store_stat_fields();
+      if ((err= stat_file->ha_update_row(record[1], record[0])) &&
+           err != HA_ERR_RECORD_IS_THE_SAME)
+        return TRUE;
+    }
+    else
+    {
+      store_stat_fields();
+      if ((err= stat_file->ha_write_row(record[0])))
+	return TRUE;
+    } 
+    return FALSE;
+  }
+};
+
+
+/*
+  An object of the class Table_stat is created to read statistical
+  data on tables from the statistical table table_stat or to update
+  table_stat with such statistical data.
+  Rows from the statistical table are read and updated always by
+  primary key. 
+*/
+
+class Table_stat: public Stat_table
+{
+private:
+  Field *db_name_field;     /* Field for the column table_stat.db_name */
+  Field *table_name_field;  /* Field for the column table_stat.table_name */
+
+public:
+
+  /*
+    @details
+    The constructor 'tunes' the private and protected members of the
+    constructed object for the statistical table table_stat to read/update
+    statistics on table 'tab'. The TABLE structure for the table table_stat
+    must be passed as a value for the parameter 'stat'.
+  */
+  Table_stat(TABLE *stat, TABLE *tab) :Stat_table(stat, tab)
+  {
+    db_name_field= stat_table->field[TABLE_STAT_DB_NAME];
+    table_name_field= stat_table->field[TABLE_STAT_TABLE_NAME];
+  }
+
+  /* 
+    @brief
+    Set the key fields for the statistical table table_stat
+
+    @details
+    The function sets the values of the fields db_name and table_name
+    in the record buffer for the statistical table table_stat.
+    These fields comprise the primary key for the table.
+
+    @note
+    The function is supposed to be called before any use of the  
+    method find_stat for an object of the Table_stat class. 
+  */
+  void set_key_fields()
+  {
+    db_name_field->store(db_name, db_name_len, &my_charset_bin);
+    table_name_field->store(table_name, table_name_len, &my_charset_bin);
+  }
+
+  /* 
+    @brief
+    Store statistical data into statistical fields of table_stat
+
+    @details
+    This implementation of a purely virtual method sets the value of the
+    column 'cardinality' of the statistical table table_stat according to
+    the value of the flag write_stat.cardinality_is_null and the value of
+    the field write_stat.cardinality' from the TABLE structure for 'table'.
+  */    
+  void store_stat_fields()
+  {
+    Field *stat_field= stat_table->field[TABLE_STAT_CARDINALITY];
+    if (table->write_stat.cardinality_is_null)
+      stat_field->set_null();
+    else
+    {
+      stat_field->set_notnull();
+      stat_field->store(table->write_stat.cardinality);
+    }
+  }
+
+  /* 
+    @brief
+    Read statistical data from statistical fields of table_stat
+
+    @details
+    This implementation of a purely virtual method first looks for a record
+    the statistical table table_stat by its primary key set the record
+    buffer with the help of Table_stat::set_key_fields.  Then, if the row is
+    found the function reads the value of the column 'cardinality' of the table
+    table_stat and sets the value of the flag read_stat.cardinality_is_null
+    and the value of the field read_stat.cardinality' from the TABLE structure
+    for 'table' accordingly.
+  */    
+  void get_stat_values()
+  {
+    table->read_stat.cardinality_is_null= TRUE;
+    table->read_stat.cardinality= 0;
+    if (find_stat())
+    {
+      Field *stat_field= stat_table->field[TABLE_STAT_CARDINALITY];
+      if (!stat_field->is_null())
+      {
+        table->read_stat.cardinality_is_null= FALSE;
+        table->read_stat.cardinality= stat_field->val_int();
+      }
+    }
+  } 
+
+};
+
+
+/*
+  An object of the class Column_stat is created to read statistical data
+  on table columns from the statistical table column_stat or to update
+  column_stat with such statistical data.
+  Rows from the statistical table are read and updated always by 
+  primary key.
+*/ 
+
+class Column_stat: public Stat_table
+{
+private:
+  Field *db_name_field;     /* Field for the column column_stat.db_name */
+  Field *table_name_field;  /* Field for the column column_stat.table_name */
+  Field *column_name_field; /* Field for the column column_stat.column_name */
+
+  Field *table_field;  /* Field from 'table' to read /update statistics on */
+
+public:
+
+  /*
+    @details
+    The constructor 'tunes' the private and protected members of the
+    constructed object for the statistical table column_stat to read/update
+    statistics on fields of the table 'tab'. The TABLE structure for the table
+    column_stat must be passed as a value for the parameter 'stat'.
+  */
+  Column_stat(TABLE *stat, TABLE *tab) :Stat_table(stat, tab)
+  {
+    db_name_field= stat_table->field[COLUMN_STAT_DB_NAME];
+    table_name_field= stat_table->field[COLUMN_STAT_TABLE_NAME];
+    column_name_field= stat_table->field[COLUMN_STAT_COLUMN_NAME];
+  } 
+
+  /* 
+    @brief
+    Set the key fields for the statistical table column_stat
+
+    @param
+    column    Field for the 'table' column to read/update statistics on
+
+    @details
+    The function sets the values of the fields db_name, table_name and
+    column_name in the record buffer for the statistical table column_stat.
+    These fields comprise the primary key for the table.
+
+    @note
+    The function is supposed to be called before any use of the  
+    method find_stat for an object of the Column_stat class.
+  */
+  void set_key_fields(Field *column)
+  {
+    db_name_field->store(db_name, db_name_len, &my_charset_bin);
+    table_name_field->store(table_name, table_name_len, &my_charset_bin);
+    table_field= column;
+    const char *column_name= column->field_name;
+    column_name_field->store(column_name, strlen(column_name), &my_charset_bin);  
+  }
+
+  /* 
+    @brief
+    Store statistical data into statistical fields of column_stat
+
+    @details
+    This implementation of a purely virtual method sets the value of the
+    columns 'min_value', 'max_value', 'nulls_ratio', 'avg_length' and
+    'avg_frequency' of the stistical table columns_stat according to the
+    contents of the bitmap write_stat.column_stat_nulls and the values
+    of the fields min_value, max_value, nulls_ratio, avg_length and
+    avg_frequency of the structure write_stat from the Field structure
+    for the field 'table_field'.
+    The value of the k-th column in the table columns_stat is set to NULL
+    if the k-th bit in the bitmap 'column_stat_nulls' is set to 1. 
+
+    @note
+    A value from the field min_value/max_value is always converted
+    into a utf8 string. If the length of the column 'min_value'/'max_value'
+    is less than the length of the string the string is trimmed to fit the
+    length of the column. 
+  */    
+  void store_stat_fields()
+  {
+    char buff[MAX_FIELD_WIDTH];
+    String val(buff, sizeof(buff), &my_charset_utf8_bin);
+
+    for (uint i= COLUMN_STAT_MIN_VALUE; i <= COLUMN_STAT_AVG_FREQUENCY; i++)
+    {  
+      Field *stat_field= stat_table->field[i];
+      if (check_null_for_write_column_stat_value(table_field, i))
+        stat_field->set_null();
+      else
+      {
+        stat_field->set_notnull();
+        switch (i) {
+        case COLUMN_STAT_MIN_VALUE:
+          if (table_field->type() == MYSQL_TYPE_BIT)
+            stat_field->store(table_field->write_stat.min_value->val_int());
+          else
+          {
+            table_field->write_stat.min_value->val_str(&val);
+            stat_field->store(val.ptr(), val.length(), &my_charset_utf8_bin);
+          }
+          break;
+        case COLUMN_STAT_MAX_VALUE:
+          if (table_field->type() == MYSQL_TYPE_BIT)
+            stat_field->store(table_field->write_stat.max_value->val_int());
+          else
+          {
+            table_field->write_stat.max_value->val_str(&val);
+            stat_field->store(val.ptr(), val.length(), &my_charset_utf8_bin);
+          }
+          break;
+        case COLUMN_STAT_NULLS_RATIO:
+          stat_field->store(table_field->write_stat.nulls_ratio);
+          break;
+        case COLUMN_STAT_AVG_LENGTH:
+          stat_field->store(table_field->write_stat.avg_length);
+          break;
+        case COLUMN_STAT_AVG_FREQUENCY:
+          stat_field->store(table_field->write_stat.avg_frequency);
+          break;            
+        }
+      }
+    }
+  }
+
+  /* 
+    @brief
+    Read statistical data from statistical fields of column_stat
+
+    @details
+    This implementation of a purely virtual method first looks for a record
+    the statistical table column_stat by its primary key set the record
+    buffer with the help of Column_stat::set_key_fields. Then, if the row is
+    found, the function reads the values of the columns 'min_value',
+    'max_value', 'nulls_ratio', 'avg_length' and 'avg_frequency' of the
+    table column_stat and sets accordingly the value of the bitmap 
+    read_stat.column_stat_nulls' and the values of the fields min_value,
+    max_value, nulls_ratio, avg_length and avg_frequency of the structure
+    read_stat from the Field structure for the field 'table_field'.
+  */    
+  void get_stat_values()
+  {
+    set_nulls_for_read_column_stat_values(table_field);
+
+    if (table_field->read_stat.min_value)
+      table_field->read_stat.min_value->set_null();
+    if (table_field->read_stat.max_value)
+      table_field->read_stat.max_value->set_null();
+
+    if (find_stat())
+    {
+      char buff[MAX_FIELD_WIDTH];
+      String val(buff, sizeof(buff), &my_charset_utf8_bin);
+
+      for (uint i= COLUMN_STAT_MIN_VALUE; i <= COLUMN_STAT_AVG_FREQUENCY; i++)
+      {  
+        Field *stat_field= stat_table->field[i];
+
+        if (!stat_field->is_null() &&
+            (i > COLUMN_STAT_MAX_VALUE ||
+             (i == COLUMN_STAT_MIN_VALUE && table_field->read_stat.min_value) ||
+             (i == COLUMN_STAT_MAX_VALUE && table_field->read_stat.max_value)))
+        {
+          set_not_null_for_read_column_stat_value(table_field, i);
+
+          switch (i) {
+          case COLUMN_STAT_MIN_VALUE:
+            stat_field->val_str(&val);
+            table_field->read_stat.min_value->store(val.ptr(), val.length(),
+                                                     &my_charset_utf8_bin);
+            break;
+          case COLUMN_STAT_MAX_VALUE:
+            stat_field->val_str(&val);
+            table_field->read_stat.max_value->store(val.ptr(), val.length(),
+                                                    &my_charset_utf8_bin);
+            break;
+          case COLUMN_STAT_NULLS_RATIO:
+            table_field->read_stat.nulls_ratio= stat_field->val_real();
+            break;
+          case COLUMN_STAT_AVG_LENGTH:
+            table_field->read_stat.avg_length= stat_field->val_real();
+            break;
+          case COLUMN_STAT_AVG_FREQUENCY:
+            table_field->read_stat.avg_frequency= stat_field->val_real();
+            break;            
+          }
+        }
+      }
+    }
+  }
+
+};
+
+
+/*
+  An object of the class Index_stat is created to read statistical
+  data on index prefixes from the statistical table index_stat or
+  to update index_stat with such statistical data.
+  Rows from the statistical table are read and updated always by 
+  primary key.
+*/ 
+
+class Index_stat: public Stat_table
+{
+private:
+  Field *db_name_field;      /* Field for the column index_stat.db_name */
+  Field *table_name_field;   /* Field for the column index_stat.table_name */
+  Field *index_name_field;   /* Field for the column index_stat.table_name */
+  Field *prefix_arity_field; /* Field for the column index_stat.prefix_arity */
+
+  KEY *table_key_info;  /* Info on the index to read/update statistics on */
+  uint prefix_arity; /* Number of components of the index prefix of interest */
+
+public:
+
+  /*
+    @details
+    The constructor 'tunes' the private and protected members of the
+    constructed object for the statistical table index_stat to read/update
+    statistics on prefixes of different indexes of the table 'tab'.
+    The TABLE structure for the table index_stat must be passed as a value
+    for the parameter 'stat'.
+  */
+  Index_stat(TABLE *stat, TABLE *tab) :Stat_table(stat, tab)
+  {
+    db_name_field= stat_table->field[INDEX_STAT_DB_NAME];
+    table_name_field= stat_table->field[INDEX_STAT_TABLE_NAME];
+    index_name_field= stat_table->field[INDEX_STAT_INDEX_NAME];
+    prefix_arity_field= stat_table->field[INDEX_STAT_PREFIX_ARITY];
+    
+  } 
+
+  /* 
+    @brief
+    Set the key fields for the statistical table index_stat
+
+    @param
+    index_info   Info for the index of 'table' to read/update statistics on
+    @param
+    index_prefix_arity Number of components in the index prefix of interest
+
+
+    @details
+    The function sets the values of the fields db_name, table_name and
+    index_name, prefix_arity in the record buffer for the statistical
+    table index_stat. These fields comprise the primary key for the table. 
+
+    @note
+    The function is supposed to be called before any use of the  
+    method find_stat for an object of the Index_stat class.
+  */
+    void set_key_fields(KEY *index_info, uint index_prefix_arity)
+  {
+    db_name_field->store(db_name, db_name_len, &my_charset_bin);
+    table_name_field->store(table_name, table_name_len, &my_charset_bin);
+    table_key_info= index_info;
+    char *index_name= index_info->name;
+    index_name_field->store(index_name, strlen(index_name), &my_charset_bin);
+    prefix_arity= index_prefix_arity; 
+    prefix_arity_field->store(index_prefix_arity, TRUE);  
+  }
+
+  /* 
+    @brief
+    Store statistical data into statistical fields of tableindex_stat
+
+    @details
+    This implementation of a purely virtual method sets the value of the
+    column 'avg_frequency' of the statistical table index_stat according to
+    the value of write_stat.avg_frequency[Index_stat::prefix_arity]
+    from the KEY_INFO structure 'table_key_info'.
+    If the value of write_stat. avg_frequency[Index_stat::prefix_arity] is
+    equal  to 0, the value of the column is set to NULL.
+  */    
+  void store_stat_fields()
+  {
+    Field *stat_field= stat_table->field[INDEX_STAT_AVG_FREQUENCY]; 
+    double avg_frequency=
+             table_key_info->write_stat.avg_frequency[prefix_arity-1];
+    if (avg_frequency == 0)
+      stat_field->set_null();
+    else
+    {
+      stat_field->set_notnull();
+      stat_field->store(avg_frequency);
+    }
+  }
+
+  /* 
+    @brief
+    Read statistical data from statistical fields of index_stat
+
+    @details
+    This implementation of a purely virtual method first looks for a record the
+    statistical table index_stat by its primary key set the record buffer with
+    the help of Index_stat::set_key_fields. If the row is found the function
+    reads the value of the column 'avg_freguency' of the table index_stat and
+    sets the value of read_stat.avg_frequency[Index_stat::prefix_arity]
+    from the KEY_INFO structure 'table_key_info' accordingly. If the value of
+    the column is NULL, read_stat.avg_frequency[Index_stat::prefix_arity] is
+    set to 0. Otherwise, read_stat.avg_frequency[Index_stat::prefix_arity] is
+    set to the value of the column.
+  */    
+  void get_stat_values()
+  {
+    double avg_frequency= 0;
+    if(find_stat())
+    {
+      Field *stat_field= stat_table->field[INDEX_STAT_AVG_FREQUENCY];
+      if (!stat_field->is_null())
+          avg_frequency= stat_field->val_real();
+    }
+    table_key_info->read_stat.avg_frequency[prefix_arity-1]= avg_frequency;
+  }  
+
+};
+
+
+/*
+  The class Count_distinct_field is a helper class used to calculate
+  the number of distinct values for a column. The class employs the
+  Unique class for this purpose.
+  The class Count_distinct_field is used only by the function
+  collect_statistics_from_table to calculate the values for 
+  column avg_frequency of the statistical table column_stat.
+*/
+    
+class Count_distinct_field: public Sql_alloc
+{
+protected:
+
+  /* Field for which the number of distinct values is to be find out */
+  Field *table_field;  
+  Unique *tree;       /* The helper object to contain distinct values */
+  uint tree_key_length; /* The length of the keys for the elements of 'tree */
+
+public:
+
+  /*
+    @param
+    field               Field for which the number of distinct values is 
+                        to be find out
+    @param
+    max_heap_table_size The linit for the memory used by the RB tree container
+                        of the constructed Unique object 'tree' 
+
+    @details
+    The constructor sets the values of 'table_field' and 'tree_key_length',
+    and then calls the 'new' operation to create a Unique object for 'tree'.
+    The type of 'field' and the value max_heap_table_size of determine the set
+    of the parameters to be passed to the constructor of the Unique object. 
+  */  
+  Count_distinct_field(Field *field, uint max_heap_table_size)
+  {
+    qsort_cmp2 compare_key;
+    void* cmp_arg;
+    enum enum_field_types f_type= field->type();
+
+    table_field= field;
+    tree_key_length= field->pack_length();
+
+    if ((f_type == MYSQL_TYPE_VARCHAR) ||
+	(!field->binary() && (f_type == MYSQL_TYPE_STRING ||
+                              f_type == MYSQL_TYPE_VAR_STRING)))
+    {
+      compare_key= (qsort_cmp2) simple_str_key_cmp;
+      cmp_arg= (void*) field;      
+    }
+    else
+    {
+      cmp_arg= (void*) &tree_key_length;
+      compare_key= (qsort_cmp2) simple_raw_key_cmp;
+    }
+        
+    tree= new Unique(compare_key, cmp_arg,
+                     tree_key_length, max_heap_table_size);
+  }
+
+  virtual ~Count_distinct_field()
+  {
+    delete tree;
+    tree= NULL;
+  }
+
+  /* 
+    @brief
+    Check whether the Unique object tree has been succesfully created
+  */
+  bool exists()
+  {
+    return (tree != NULL);
+  }
+
+  /*
+    @brief
+    Add the value of 'field' to the container of the Unique object 'tree'
+  */
+  virtual bool add()
+  {
+    return tree->unique_add(table_field->ptr);
+  }
+  
+  /*
+    @brief
+    Calculate the number of elements accumulated in the container of 'tree'
+  */
+  ulonglong get_value()
+  {
+    ulonglong count;
+    if (tree->elements == 0)
+      return (ulonglong) tree->elements_in_tree();
+    count= 0;  
+    tree->walk(count_distinct_walk, (void*) &count);
+    return count;
+  }
+};
+
+
+/* 
+  The class Count_distinct_field_bit is derived from the class 
+  Count_distinct_field to be used only for fields of the MYSQL_TYPE_BIT type.
+  The class provides a different implementation for the method add 
+*/
+
+class Count_distinct_field_bit: public Count_distinct_field
+{
+public:
+  Count_distinct_field_bit(Field *field, uint max_heap_table_size)
+    :Count_distinct_field(field, max_heap_table_size) {}
+  bool add()
+  {
+    longlong val= table_field->val_int();   
+    return tree->unique_add(&val);
+  }
+};
+
+
+/* 
+  The class Index_prefix_calc is a helper class used to calculate the values
+  for the column 'avg_frequency' of the statistical table index_stat.
+  For any table t from the database db and any k-component prefix of the
+  index i for this table the row from index_stat with the primary key
+  (db,t,i,k) must contain in the column 'avg_frequency' either NULL or 
+  the number that is the ratio of N and V, where N is the number of index
+  entries without NULL values in the first k components of the index i,
+  and V is the number of distinct tuples composed of the first k components
+  encountered among these index entries.  
+  Currently the objects of this class are used only by the function
+  collect_statistics_for_index. 
+*/
+
+class Index_prefix_calc: public Sql_alloc
+{
+private:
+  /* Table containing index specified by index_info */
+  TABLE *index_table;  
+  /* Info for the index i for whose prefix 'avg_frequency' is calculated */
+  KEY *index_info;  
+  /* The maximum number of the components in the prefixes of interest */   
+  uint prefixes; 
+  bool empty;  
+
+  /* This structure is created for every k components of the index i */
+  class Prefix_calc_state
+  {
+  public:
+    /* 
+      The number of the scanned index entries without nulls 
+      in the first k components
+    */
+    ulonglong entry_count;
+    /* 
+      The number if the scanned index entries without nulls with 
+      the last encountered k-component prefix
+    */
+    ulonglong prefix_count;
+    /* The values of the last encoutered k-component prefix */
+    Cached_item *last_prefix;
+  };
+
+  /* 
+    Array of structures used to calculate 'avg_frequency' for different
+    prefixes of the index i
+  */   
+  Prefix_calc_state *calc_state;
+    
+public:
+  Index_prefix_calc(TABLE *table, KEY *key_info)
+    : index_table(table), index_info(key_info)
+  {
+    uint i;
+    Prefix_calc_state *state;
+    uint key_parts= key_info->key_parts;
+    empty= TRUE;
+    prefixes= 0;
+    if ((calc_state=
+         (Prefix_calc_state *) sql_alloc(sizeof(Prefix_calc_state)*key_parts)))
+    {
+      uint keyno= key_info-table->key_info;
+      for (i= 0, state= calc_state; i < key_parts; i++, state++)
+      {
+        /* 
+          Do not consider prefixes containing a component that is only part
+          of the field. This limitation is set to avoid fetching data when
+          calculating the values of 'avg_frequency' for prefixes.
+	*/   
+        if (!key_info->key_part[i].field->part_of_key.is_set(keyno))
+          break;
+
+        if (!(state->last_prefix=
+              new Cached_item_field(key_info->key_part[i].field)))
+          break;
+        state->entry_count= state->prefix_count= 0;
+        prefixes++;
+      }
+    }
+  }
+
+  /* 
+    @breif
+    Change the elements of calc_state after reading the next index entry
+
+    @details
+    This function is to be called at the index scan each time the next
+    index entry has been read into the record buffer.
+    For each of the index prefixes the function checks whether nulls
+    are encountered in any of the k components of the prefix.
+    If this is not the case the value of calc_state[k-1].entry_count
+    is incremented by 1. Then the function checks whether the value of
+    any of these k components has changed. If so, the value of 
+    calc_state[k-1].prefix_count is incremented by 1. 
+  */
+  void add()
+  {
+    uint i;
+    Prefix_calc_state *state;
+    uint first_changed= prefixes;
+    for (i= prefixes, state= calc_state+prefixes-1; i; i--, state--)
+    {
+      if (state->last_prefix->cmp())
+        first_changed= i-1;
+    }
+    if (empty)
+    {
+      first_changed= 0;
+      empty= FALSE;
+    }
+    for (i= 0, state= calc_state; i < prefixes; i++, state++)
+    {
+      if (state->last_prefix->null_value)
+        break;
+      if (i >= first_changed)
+        state->prefix_count++;
+      state->entry_count++;
+    }   
+  }
+
+  /*
+    @brief
+    Calculate the values of avg_frequency for all prefixes of an index
+
+    @details
+    This function is to be called after the index scan to count the number
+    of distinct index prefixes has been done. The function calculates
+    the value of avg_frequency for the index prefix with k components
+    as calc_state[k-1].entry_count/calc_state[k-1].prefix_count.
+    If calc_state[k-1].prefix_count happens to be 0, the value of
+    avg_frequency[k-1] is set to 0, i.e. is considered as unknown.
+  */
+  void get_avg_frequency()
+  {
+    uint i;
+    Prefix_calc_state *state;
+    for (i= 0, state= calc_state; i < prefixes; i++, state++)
+    {
+      if (i < prefixes)
+      {
+        index_info->write_stat.avg_frequency[i]=
+          state->prefix_count == 0 ? 0 :
+          (double) state->entry_count / state->prefix_count;
+      }
+    }
+  }       
+};
+
+
+/*
+  @brief 
+  Create fields for min/max values to collect/read column statistics
+
+  @param
+  table       Table the fields are created for
+  @param
+  for_write   Those fields are created that are used to collect statistics
+
+  @note
+  The function first allocates record buffers to store min/max values
+  for 'table's fields. Then for each table field f it creates Field structures
+  that points to these buffers rather that to the record buffer as the
+  Field object for f does. The pointers of the created fields are placed
+  either in the write_stat or in the read_stat structure of the Field
+  object for f, depending on the value of the 'for_write' parameter.
+
+  @note 
+  The buffers allocated when min/max values are used to read statistics
+  from the persistent statistical tables differ from those buffers that
+  are used when statistics on min/max values for column is collected.
+  The same is true for the fields created for min/max values.  
+*/      
+
+static
+void create_min_max_stistical_fields(TABLE *table, bool for_write)
+{
+  Field *table_field;
+  Field **field_ptr;
+  uchar *record;
+  uint rec_buff_length= table->s->rec_buff_length;
+
+  for (field_ptr= table->field; *field_ptr; field_ptr++) 
+  {
+    table_field= *field_ptr;
+    if (for_write)
+      table_field->write_stat.max_value=
+        table_field->write_stat.min_value= NULL;
+    else
+      table_field->read_stat.max_value=
+        table_field->read_stat.min_value= NULL;
+  }
+
+  if ((record= (uchar *) alloc_root(&table->mem_root, 2*rec_buff_length)))
+  {
+    for (uint i=0; i < 2; i++, record+= rec_buff_length)
+    {
+      for (field_ptr= table->field; *field_ptr; field_ptr++) 
+      {
+        Field *fld;
+        table_field= *field_ptr;
+        my_ptrdiff_t diff= record-table->record[0];
+        if (!(fld= table_field->clone(&table->mem_root, table, diff, TRUE)))
+          continue;
+        if (i == 0)
+        {
+          if (for_write)
+            table_field->write_stat.min_value= fld;
+          else
+            table_field->read_stat.min_value= fld;
+        }
+        else
+        {
+          if (for_write)
+            table_field->write_stat.max_value= fld;
+          else
+            table_field->read_stat.max_value= fld;
+        }
+      }
+    }
+  }
+}
+
+/*
+  @brief
+  Collect statistical data on an index
+
+  @param 
+  table       The table the index belongs to
+  index       The number of this index in the table
+
+  @details
+  The function collects the value of 'avg_frequency' for the prefixes
+  on an index from 'table'. The index is specified by its number.
+  If the scan is successful the calculated statistics is saved in the
+  elements of the array write_stat.avg_frequency of the KEY_INFO structure
+  for the index. The statistics for the prefix with k components is saved
+  in the element number k-1.
+
+  @retval
+  0         If the statistics has been successfully collected  
+  @retval
+  1         Otherwise
+
+  @note
+  The function collects statistics for the index prefixes for one index
+  scan during which no data is fetched from the table records. That's why
+  statistical data for prefixes that contain part of a field is not
+  collected.
+  The function employs an object of the helper class Index_prefix_calc to
+  count for each index prefix the number of index entries without nulls and
+  the number of distinct entries among them.
+ 
+*/
+
+static
+int collect_statistics_for_index(TABLE *table, uint index)
+{
+  int rc= 0;
+  KEY *key_info= &table->key_info[index];
+  ha_rows rows= 0;
+  Index_prefix_calc index_prefix_calc(table, key_info);
+  DBUG_ENTER("collect_statistics_for_index");
+
+  table->key_read= 1;
+  table->file->extra(HA_EXTRA_KEYREAD);
+
+  table->file->ha_index_init(index, TRUE);
+  rc= table->file->ha_index_first(table->record[0]);
+  while (rc != HA_ERR_END_OF_FILE)
+  {
+    if (rc)
+      break;
+    rows++;
+    index_prefix_calc.add();
+    rc= table->file->ha_index_next(table->record[0]);
+  }
+  table->key_read= 0;
+  table->file->ha_index_end();
+
+  rc= (rc == HA_ERR_END_OF_FILE) ? 0 : 1;
+
+  if (!rc)
+    index_prefix_calc.get_avg_frequency();
+
+  DBUG_RETURN(rc);            
+}
+
+/*
+  @brief 
+  Collect statistical data for a table
+
+  @param
+  thd         The thread handle
+  @param
+  table       The table to collect statistics on
+
+  @details
+  The function collects data for various statistical characteristics on
+  the table 'table'. These data is saved in the internal fields that could
+  be reached from 'table'. The data is prepared to be saved in the persistent
+  statistical table by the function update_statistics_for_table.
+  The collected statistical values are not placed in the same fields that
+  keep the statistical data used by the optimizer. Therefore, at any time,
+  there is no collision between the statistics being collected and the one
+  used by the optimizer to look for optimal query execution plans for other
+  clients.
+
+  @retval
+  0         If the statistics has been successfully collected  
+  @retval
+  1         Otherwise
+
+  @note
+  The function first collects statistical data for statistical characteristics
+  to be saved in the statistical tables table_stat and column_stat. To do this
+  it performs a full table scan of 'table'. At this scan the function collects
+  statistics on each column of the table and count the total number of the
+  scanned rows. To calculate the value of 'avg_frequency' for a column the
+  function constructs an object of the helper class Count_distinct_field
+  (or its derivation). Currently this class cannot count the number of
+  distinct values for blob columns. So the value of 'avg_frequency' for
+  blob columns is always null.
+  After the full table scan the function calls collect_statistics_for_index
+  for each table index. The latter performs full index scan for each index.
+
+  @note
+  Currently the statistical data is collected indiscriminately for all
+  columns/indexes of 'table', for all statistical characteristics.
+  TODO. Collect only specified statistical characteristics for specified
+  columns/indexes.
+
+  @note
+  Currently the process of collecting statistical data is not optimized.
+  For example, 'avg_frequency' for a column could be copied from the
+  'avg_frequency' collected for an index if this column is used as the
+  first component of the index. Min and min values for this column could
+  be extracted from the index as well.       
+*/
+
+int collect_statistics_for_table(THD *thd, TABLE *table)
+{
+  int rc;
+  Field **field_ptr;
+  Field *table_field;
+  ha_rows rows= 0;
+  handler *file=table->file; 
+
+  DBUG_ENTER("collect_statistics_for_table");
+
+  table->write_stat.cardinality_is_null= TRUE;
+  table->write_stat.cardinality= 0;
+ 
+  create_min_max_stistical_fields(table, TRUE);
+
+  for (field_ptr= table->field; *field_ptr; field_ptr++)
+  {
+    table_field= *field_ptr;
+    uint max_heap_table_size= thd->variables.max_heap_table_size;
+    set_nulls_for_write_column_stat_values(table_field);
+    table_field->nulls= 0;
+    table_field->column_total_length= 0;
+    if (table_field->flags & BLOB_FLAG)
+      table_field->count_distinct= NULL;
+    else
+    {
+      table_field->count_distinct=
+        table_field->type() == MYSQL_TYPE_BIT ?
+        new Count_distinct_field_bit(table_field, max_heap_table_size) :
+        new Count_distinct_field(table_field, max_heap_table_size);
+    }
+    if (table_field->count_distinct && 
+       !table_field->count_distinct->exists())
+      table_field->count_distinct= NULL;
+  }
+
+  bitmap_set_all(table->read_set);
+
+  /* Perform a full table scan to collect statistics on 'table's columns */
+  if (!(rc= file->ha_rnd_init(FALSE)))
+  {  
+    while ((rc= file->ha_rnd_next(table->record[0])) != HA_ERR_END_OF_FILE)
+    {
+      if (rc)
+        break;
+
+      for (field_ptr= table->field; *field_ptr; field_ptr++)
+      {
+        table_field= *field_ptr;
+        if (table_field->is_null())
+          table_field->nulls++;
+        else
+        {
+          table_field->column_total_length+= table_field->value_length();
+          if (table_field->write_stat.min_value &&
+              table_field->update_min(table_field->write_stat.min_value,
+                                      rows == table_field->nulls))
+            set_not_null_for_write_column_stat_value(table_field,
+                                                     COLUMN_STAT_MIN_VALUE);
+          if (table_field->write_stat.max_value && 
+              table_field->update_max(table_field->write_stat.max_value,
+                                      rows == table_field->nulls))
+            set_not_null_for_write_column_stat_value(table_field,
+                                                     COLUMN_STAT_MAX_VALUE);
+          if (table_field->count_distinct) 
+            table_field->count_distinct->add();          
+        }
+      }
+      rows++;
+    }
+    file->ha_rnd_end();
+  }
+  rc= rc == HA_ERR_END_OF_FILE ? 0 : 1;
+
+  /* 
+    Calculate values for all statistical characteristics on columns and
+    and for each field f of 'table' save them in the write_stat structure
+    from the Field object for f. 
+  */
+  if (!rc)
+  {
+    table->write_stat.cardinality_is_null= FALSE;
+    table->write_stat.cardinality= rows;
+
+    for (field_ptr= table->field; *field_ptr; field_ptr++)
+    {
+      table_field= *field_ptr;
+      table_field->write_stat.nulls_ratio= (double) table_field->nulls/rows;
+      table_field->write_stat.avg_length=
+        (double) table_field->column_total_length / (rows-table_field->nulls);
+      if (table_field->count_distinct)
+      {
+        table_field->write_stat.avg_frequency= 
+          (double) (rows-table_field->nulls) /
+          table_field->count_distinct->get_value(); 
+        set_not_null_for_write_column_stat_value(table_field,
+                                                 COLUMN_STAT_AVG_FREQUENCY);
+        delete table_field->count_distinct;
+        table_field->count_distinct= NULL;
+      }
+      
+      set_not_null_for_write_column_stat_value(table_field,
+                                               COLUMN_STAT_NULLS_RATIO);
+      set_not_null_for_write_column_stat_value(table_field,
+                                               COLUMN_STAT_AVG_LENGTH);
+    }
+  }
+
+  if (!rc)
+  {
+    uint keys= table->s->keys ;
+
+    /* Collect statistics for indexes */
+    for (uint i= 0; i < keys; i++)
+    {
+      if ((rc= collect_statistics_for_index(table, i)))
+        break;
+    }
+  }
+
+  DBUG_RETURN(rc);          
+}
+
+
+/*
+  @brief
+  Update statistics for a table in the persistent statistical tables
+
+  @param
+  thd         The thread handle
+  @param
+  table       The table to collect statistics on
+
+  @details
+  For each statistical table st the function looks for the rows from this
+  table that contain statistical data on 'table'. If rows with given 
+  statistical characteritics exist they are updated with the new statistical
+  values taken from internal structures for 'table'. Otherwise new rows
+  with these statistical characteristics are added into st.
+  It is assumed that values stored in the statistical tables are found and
+  saved by the function collect_statistics_for_table. 
+
+  @retval
+  0         If all statistical tables has been successfully updated  
+  @retval
+  1         Otherwise
+
+  @note
+  The function is called when executing the ANALYZE actions for 'table'.
+  The function first unlocks the opened table the statistics on which has
+  been collected, but does not closes it, so all collected statistical data
+  remains in internal structures for 'table'. Then the function opens the
+  statistical tables and writes the statistical data for 'table'into them.
+  It is not allowed just to open statistical tables for writing when some
+  other tables are locked for reading.
+  After the statistical tables have been opened they are updated one by one
+  with the new statistics on 'table'. Objects of the helper classes
+  Table_stat, Column_stat and Index_stat are employed for this. 
+  After having been updated the statistical system tables are closed.     
+*/
+
+int update_statistics_for_table(THD *thd, TABLE *table)
+{
+  TABLE_LIST tables[STATISTICS_TABLES];
+  Open_tables_state open_tables_state_backup;
+  uint i;
+  int err;
+  int rc= 0;
+  TABLE *stat_table;
+  uint keys= table->s->keys;
+
+  DBUG_ENTER("update_statistics_for_table");
+
+  bzero((char *) &tables[0], sizeof(tables));
+
+  for (i= 0; i < STATISTICS_TABLES; i++)
+  {
+    tables[i].db= (char*) "mysql";
+    tables[i].table_name= (char *) STAT_TABLE_NAME[i];
+    tables[i].alias= tables[i].table_name;
+    tables[i].lock_type= TL_WRITE;
+    if (i < STATISTICS_TABLES - 1)
+    tables[i].next_global= tables[i].next_local=
+      tables[i].next_name_resolution_table= &tables[i+1];
+  }
+  
+  if (unlock_tables_n_open_system_tables_for_write(thd,
+                                                   tables,
+                                                   &open_tables_state_backup))
+    DBUG_RETURN(1);
+   
+  /* Update the statistical table table_stat */
+  stat_table= tables[TABLE_STAT].table;
+  Table_stat table_stat(stat_table, table);
+  restore_record(stat_table, s->default_values);
+  table_stat.set_key_fields();
+  err= table_stat.update_stat();
+  if (err)
+    rc= 1;
+
+  /* Update the statistical table colum_stat */
+  stat_table= tables[COLUMN_STAT].table;
+  Column_stat column_stat(stat_table, table);
+  for (Field **field_ptr= table->field; *field_ptr; field_ptr++)
+  {
+    Field *table_field= *field_ptr;
+    restore_record(stat_table, s->default_values);
+    column_stat.set_key_fields(table_field);
+    err= column_stat.update_stat();
+    if (err & !rc)
+      rc= 1;
+  }
+
+  /* Update the statistical table index_stat */
+  stat_table= tables[INDEX_STAT].table;
+  Index_stat index_stat(stat_table, table);
+  KEY *key_info, *key_info_end;
+
+  for (key_info= table->key_info, key_info_end= table->key_info+keys;
+       key_info < key_info_end; key_info++)
+  {
+    uint key_parts= key_info->key_parts;
+    for (i= 0; i < key_parts; i++)
+    {
+      restore_record(stat_table, s->default_values);
+      index_stat.set_key_fields(key_info, i+1);
+      err= index_stat.update_stat();
+      if (err & !rc)
+        rc= 1;
+    }
+  }
+
+  close_system_tables(thd, &open_tables_state_backup);
+
+  DBUG_RETURN(rc);
+}
+
+
+/*
+  @brief
+  Read statistics for a table from the persistent statistical tables
+
+  @param
+  thd         The thread handle
+  @param
+  table       The table to read statistics on
+
+  @details
+  For each statistical table the function looks for the rows from this
+  table that contain statistical data on 'table'. If such rows is found
+  the data from statistical columns of it is read into the appropriate
+  fields of internal structures for 'table'. Later at the query processing
+  this data are supposed to be used by the optimizer. 
+  The function is called in function open_tables.
+
+  @retval
+  0         If data has been succesfully read from all statistical tables  
+  @retval
+  1         Otherwise
+
+  @note
+  The function first calls the function open_system_tables_for_read to
+  be able to read info from the statistical tables. On success the data is
+  read from one table after another after which the statistical tables are
+  closed. Objects of the helper classes Table_stat, Column_stat and Index_stat
+  are employed to read statistical data from the statistical tables. 
+  TODO. Consider a variant when statistical tables are opened and closed
+  only once for all tables, not for every table of the query as it's done
+  now.        
+*/
+
+int read_statistics_for_table(THD *thd, struct st_table *table)
+{
+  uint i;
+  TABLE *stat_table;
+  Field *table_field;
+  Field **field_ptr;
+  KEY *key_info, *key_info_end;
+  TABLE_LIST tables[STATISTICS_TABLES];
+  Open_tables_state open_tables_state_backup;
+
+  DBUG_ENTER("read_statistics_for_table");
+
+  bzero((char *) &tables[0], sizeof(tables));
+
+  for (i= 0; i < STATISTICS_TABLES; i++)
+  {
+    tables[i].db= (char*) "mysql";
+    tables[i].table_name= (char *) STAT_TABLE_NAME[i];
+    tables[i].alias= tables[i].table_name;
+    tables[i].lock_type= TL_READ;
+    if (i < STATISTICS_TABLES - 1)
+    tables[i].next_global= tables[i].next_local=
+      tables[i].next_name_resolution_table= &tables[i+1];
+  }
+  
+  if (open_system_tables_for_read(thd, tables, &open_tables_state_backup))
+    DBUG_RETURN(1);
+
+  create_min_max_stistical_fields(table, FALSE);
+ 
+  /* Read statistics from the statistical table index_stat */
+  stat_table= tables[TABLE_STAT].table;
+  Table_stat table_stat(stat_table, table);
+  table_stat.set_key_fields();
+  table_stat.get_stat_values();
+   
+  /* Read statistics from the statistical table column_stat */
+  stat_table= tables[COLUMN_STAT].table;
+  Column_stat column_stat(stat_table, table);
+  for (field_ptr= table->field; *field_ptr; field_ptr++)
+  {
+    table_field= *field_ptr;
+    column_stat.set_key_fields(table_field);
+    column_stat.get_stat_values();
+  }
+
+  /* Read statistics from the statistical table index_stat */
+  stat_table= tables[INDEX_STAT].table;
+  Index_stat index_stat(stat_table, table);
+  for (key_info= table->key_info, key_info_end= key_info+table->s->keys;
+       key_info < key_info_end; key_info++)
+  {
+
+    for (i= 0; i < key_info->key_parts; i++)
+    {
+      index_stat.set_key_fields(key_info, i+1);
+      index_stat.get_stat_values();
+    }
+  }
+      
+  close_system_tables(thd, &open_tables_state_backup);
+
+  DBUG_RETURN(0);
+}

=== added file 'sql/sql_statistics.h'
--- a/sql/sql_statistics.h	1970-01-01 00:00:00 +0000
+++ b/sql/sql_statistics.h	2012-01-05 01:51:53 +0000
@@ -0,0 +1,63 @@
+/* Copyright 2006-2008 MySQL AB, 2008 Sun Microsystems, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; version 2 of the License.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA */
+
+#ifndef SQL_STATISTICS_H
+#define SQL_STATISTICS_H
+
+/* 
+  These enumeration types comprise the dictionary of three
+  statistical tables table_stat, column_stat and index_stat
+  as they defined in ../scripts/mysql_system_tables.sql.
+
+  It would be nice if the declarations of these types were
+  generated automatically by the table definitions.   
+*/
+
+enum enum_stat_tables
+{
+  TABLE_STAT,
+  COLUMN_STAT,
+  INDEX_STAT,
+};
+
+enum enum_table_stat_col
+{
+  TABLE_STAT_DB_NAME,
+  TABLE_STAT_TABLE_NAME,
+  TABLE_STAT_CARDINALITY
+};
+
+enum enum_column_stat_col
+{
+  COLUMN_STAT_DB_NAME,
+  COLUMN_STAT_TABLE_NAME,
+  COLUMN_STAT_COLUMN_NAME,
+  COLUMN_STAT_MIN_VALUE,
+  COLUMN_STAT_MAX_VALUE,
+  COLUMN_STAT_NULLS_RATIO,
+  COLUMN_STAT_AVG_LENGTH,
+  COLUMN_STAT_AVG_FREQUENCY
+};
+
+enum enum_index_stat_col
+{
+  INDEX_STAT_DB_NAME,
+  INDEX_STAT_TABLE_NAME,
+  INDEX_STAT_INDEX_NAME,
+  INDEX_STAT_PREFIX_ARITY,
+  INDEX_STAT_AVG_FREQUENCY
+};
+
+#endif /* SQL_STATISTICS_H */

=== modified file 'sql/sql_table.cc'
--- a/sql/sql_table.cc	2011-12-11 09:34:44 +0000
+++ b/sql/sql_table.cc	2012-01-05 01:51:53 +0000
@@ -4692,6 +4692,7 @@
   Protocol *protocol= thd->protocol;
   LEX *lex= thd->lex;
   int result_code;
+  int compl_result_code;
   bool need_repair_or_alter= 0;
   DBUG_ENTER("mysql_admin_table");
   DBUG_PRINT("enter", ("extra_open_options: %u", extra_open_options));
@@ -4946,9 +4947,22 @@
       }
     }
 
-    DBUG_PRINT("admin", ("calling operator_func '%s'", operator_name));
-    result_code = (table->table->file->*operator_func)(thd, check_opt);
-    DBUG_PRINT("admin", ("operator_func returned: %d", result_code));
+    result_code= compl_result_code= 0;
+    if (operator_func != &handler::ha_analyze ||
+        thd->variables.optimizer_use_stat_tables < 3)
+    {
+      DBUG_PRINT("admin", ("calling operator_func '%s'", operator_name));
+      result_code = (table->table->file->*operator_func)(thd, check_opt);
+      DBUG_PRINT("admin", ("operator_func returned: %d", result_code));
+    }
+
+    if (operator_func == &handler::ha_analyze &&
+	thd->variables.optimizer_use_stat_tables > 0)
+    {
+      if (!(compl_result_code=
+            collect_statistics_for_table(thd, table->table)))
+        compl_result_code= update_statistics_for_table(thd, table->table);
+    }
 
     if (result_code == HA_ADMIN_NOT_IMPLEMENTED && need_repair_or_alter)
     {
@@ -4958,6 +4972,7 @@
       */
       result_code= admin_recreate_table(thd, table);
     }
+
 send_result:
 
     lex->cleanup_after_one_table_open();

=== modified file 'sql/structs.h'
--- a/sql/structs.h	2011-12-11 09:34:44 +0000
+++ b/sql/structs.h	2012-01-05 01:51:53 +0000
@@ -102,6 +102,31 @@
     For temporary heap tables this member is NULL.
   */
   ulong *rec_per_key;
+
+   /* Statistical data on an index prefixes */
+  class Index_statistics
+  {
+  public:
+    /*
+      The k-th element of this array contains the ratio N/D, 
+      where N is the number of index entries without nulls 
+      in the first k components, and D is the number of distinct
+      k-component prefixes among them 
+    */
+    double *avg_frequency;
+  };
+
+  /*
+    This structure is used for statistical data on the index
+    that has been read from the statistical table index_stat
+  */ 
+  Index_statistics read_stat;
+  /*
+    This structure is used for statistical data on the index that
+    is collected by the function collect_statistics_for_table
+  */
+  Index_statistics write_stat;
+ 
   union {
     int  bdb_return_if_eq;
   } handler;

=== modified file 'sql/table.cc'
--- a/sql/table.cc	2011-12-11 17:28:05 +0000
+++ b/sql/table.cc	2012-01-05 01:51:53 +0000
@@ -489,6 +489,12 @@
              my_tolower(ci, name[2]) == 'm' &&
              my_tolower(ci, name[3]) == 'e') ||
 
+            /* one of mysql.*_stat tables */
+            (my_tolower(ci, name[length-4]) == 's' &&
+             my_tolower(ci, name[length-3]) == 't' &&
+             my_tolower(ci, name[length-2]) == 'a' &&
+             my_tolower(ci, name[length-1]) == 't') ||
+           
             /* mysql.event table */
             (my_tolower(ci, name[0]) == 'e' &&
              my_tolower(ci, name[1]) == 'v' &&
@@ -698,6 +704,8 @@
   uchar *disk_buff, *strpos, *null_flags, *null_pos, *options;
   uchar *buff= 0;
   ulong pos, record_offset, *rec_per_key, rec_buff_length;
+  double *read_avg_frequency= 0;
+  double *write_avg_frequency= 0;
   handler *handler_file= 0;
   KEY	*keyinfo;
   KEY_PART_INFO *key_part;
@@ -812,7 +820,13 @@
   if (!(rec_per_key= (ulong*) alloc_root(&share->mem_root,
                                          sizeof(ulong)*key_parts)))
     goto err;
-
+  if (!(read_avg_frequency= (double*) alloc_root(&share->mem_root,
+                                                 sizeof(double)*key_parts)))
+    goto err;
+  if (!(write_avg_frequency= (double*) alloc_root(&share->mem_root,
+                                                  sizeof(double)*key_parts)))
+    goto err;
+  
   for (i=0 ; i < keys ; i++, keyinfo++)
   {
     if (new_frm_ver >= 3)
@@ -835,9 +849,13 @@
 
     keyinfo->key_part=	 key_part;
     keyinfo->rec_per_key= rec_per_key;
+    keyinfo->read_stat.avg_frequency= read_avg_frequency;
+    keyinfo->write_stat.avg_frequency= write_avg_frequency; 
     for (j=keyinfo->key_parts ; j-- ; key_part++)
     {
       *rec_per_key++=0;
+      *read_avg_frequency++= 0;
+      *write_avg_frequency++= 0;
       key_part->fieldnr=	(uint16) (uint2korr(strpos) & FIELD_NR_MASK);
       key_part->offset= (uint) uint2korr(strpos+2)-1;
       key_part->key_type=	(uint) uint2korr(strpos+5);

=== modified file 'sql/table.h'
--- a/sql/table.h	2011-12-11 17:28:05 +0000
+++ b/sql/table.h	2012-01-05 01:51:53 +0000
@@ -747,6 +747,25 @@
   */
   query_id_t	query_id;
 
+  /* Statistical data on a table */
+  class Table_statistics
+  {
+  public:
+    my_bool cardinality_is_null;  /* TRUE if the cardinality is unknown */
+    ha_rows cardinality;          /* Number of rows in the table        */
+  };
+
+  /*
+    This structure is used for statistical data on the table
+    that has been read from the statistical table table_stat
+  */ 
+  Table_statistics read_stat;
+  /*
+    This structure is used for statistical data on the table that
+    is collected by the function collect_statistics_for_table
+  */
+  Table_statistics write_stat;
+
   /* 
     For each key that has quick_keys.is_set(key) == TRUE: estimate of #records
     and max #key parts that range access would use.



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