~drizzle-trunk/drizzle/development

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DROP TABLE IF EXISTS t0,t1,t2,t3,t4,t5;
select * from information_schema.SCHEMATA where schema_name > 'm';
CATALOG_NAME	SCHEMA_NAME	DEFAULT_CHARACTER_SET_NAME	DEFAULT_COLLATION_NAME	SQL_PATH
NULL	mysql	utf8	utf8_general_ci	NULL
NULL	test	utf8	utf8_general_ci	NULL
select schema_name from information_schema.schemata;
schema_name
information_schema
mysql
test
show databases like 't%';
Database (t%)
test
show databases;
Database
information_schema
mysql
test
create database mysqltest;
create table mysqltest.t1(a int, b VARCHAR(30), KEY string_data (b));
create table test.t2(a int);
create table t3(a int, KEY a_data (a));
create table mysqltest.t4(a int);
create table t5 (id int auto_increment primary key);
insert into t5 values (10);
select table_name from information_schema.TABLES
where table_schema = "mysqltest" and table_name like "t%";
table_name
t1
t4
select * from information_schema.STATISTICS where TABLE_SCHEMA = "mysqltest";
TABLE_CATALOG	TABLE_SCHEMA	TABLE_NAME	NON_UNIQUE	INDEX_SCHEMA	INDEX_NAME	SEQ_IN_INDEX	COLUMN_NAME	COLLATION	CARDINALITY	SUB_PART	PACKED	NULLABLE	INDEX_TYPE	COMMENT	INDEX_COMMENT
NULL	mysqltest	t1	1	mysqltest	string_data	1	b	A	0	NULL	NULL	YES	BTREE		
show tables like 't%';
Tables_in_test (t%)
t2
t3
t5
show full columns from t3 like "a%";
Field	Type	Collation	Null	Key	Default	Extra	Privileges	Comment
a	int	NULL	YES	MUL	NULL		#	
select * from information_schema.COLUMNS where table_name="t1"
and column_name= "a";
TABLE_CATALOG	TABLE_SCHEMA	TABLE_NAME	COLUMN_NAME	ORDINAL_POSITION	COLUMN_DEFAULT	IS_NULLABLE	DATA_TYPE	CHARACTER_MAXIMUM_LENGTH	CHARACTER_OCTET_LENGTH	NUMERIC_PRECISION	NUMERIC_SCALE	CHARACTER_SET_NAME	COLLATION_NAME	COLUMN_TYPE	COLUMN_KEY	EXTRA	PRIVILEGES	COLUMN_COMMENT	STORAGE	FORMAT
NULL	mysqltest	t1	a	1	NULL	YES	int	NULL	NULL	10	0	NULL	NULL	int					Default	Default
select table_name, column_name, privileges from information_schema.columns 
where table_schema = 'mysqltest' and table_name = 't1';
table_name	column_name	privileges
t1	a	
t1	b	
show columns from mysqltest.t1;
Field	Type	Null	Key	Default	Extra
a	int	YES		NULL	
b	varchar(30)	YES	MUL	NULL	
drop tables mysqltest.t4, mysqltest.t1, t2, t3, t5;
drop database mysqltest;
select * from information_schema.CHARACTER_SETS
where CHARACTER_SET_NAME like 'latin1%';
CHARACTER_SET_NAME	DEFAULT_COLLATE_NAME	DESCRIPTION	MAXLEN
select * from information_schema.COLLATIONS
where COLLATION_NAME like 'latin1%';
COLLATION_NAME	CHARACTER_SET_NAME	ID	IS_DEFAULT	IS_COMPILED	SORTLEN
select * from information_schema.COLLATION_CHARACTER_SET_APPLICABILITY
where COLLATION_NAME like 'latin1%';
COLLATION_NAME	CHARACTER_SET_NAME
select * from information_schema.table_names;
ERROR 42S02: Unknown table 'table_names' in information_schema
select column_type from information_schema.columns
where table_schema="information_schema" and table_name="COLUMNS" and
(column_name="character_set_name" or column_name="collation_name");
column_type
varchar(64)
varchar(64)
select TABLE_ROWS from information_schema.tables where 
table_schema="information_schema" and table_name="COLUMNS";
TABLE_ROWS
NULL
select table_type from information_schema.tables
where table_schema="mysql" and table_name="user";
table_type
select table_schema,table_name, column_name from
information_schema.columns 
where data_type = 'longtext';
table_schema	table_name	column_name
select table_name, column_name, data_type from information_schema.columns
where data_type = 'datetime';
table_name	column_name	data_type
TABLES	CREATE_TIME	datetime
TABLES	UPDATE_TIME	datetime
TABLES	CHECK_TIME	datetime
INNODB_TRX	trx_started	datetime
INNODB_TRX	trx_wait_started	datetime
SELECT COUNT(*) FROM INFORMATION_SCHEMA.TABLES A
WHERE NOT EXISTS 
(SELECT * FROM INFORMATION_SCHEMA.COLUMNS B
WHERE A.TABLE_SCHEMA = B.TABLE_SCHEMA
AND A.TABLE_NAME = B.TABLE_NAME);
COUNT(*)
0
create table t1
( x_bigint BIGINT,
x_integer INTEGER,
x_int int,
x_decimal DECIMAL(5,3),
x_numeric NUMERIC(5,3),
x_real REAL,
x_float FLOAT,
x_double_precision DOUBLE PRECISION );
SELECT COLUMN_NAME, CHARACTER_MAXIMUM_LENGTH, CHARACTER_OCTET_LENGTH
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME= 't1';
COLUMN_NAME	CHARACTER_MAXIMUM_LENGTH	CHARACTER_OCTET_LENGTH
x_bigint	NULL	NULL
x_integer	NULL	NULL
x_int	NULL	NULL
x_decimal	NULL	NULL
x_numeric	NULL	NULL
x_real	NULL	NULL
x_float	NULL	NULL
x_double_precision	NULL	NULL
drop table t1;
SELECT table_schema, count(*) FROM information_schema.TABLES
WHERE table_name NOT LIKE 'ndb_%' AND table_name NOT LIKE 'falcon%' GROUP BY TABLE_SCHEMA;
table_schema	count(*)
information_schema	23
show create database information_schema;
Database	Create Database
information_schema	CREATE DATABASE `information_schema`
create table t1(f1 LONGBLOB, f2 LONGTEXT);
select column_name,data_type,CHARACTER_OCTET_LENGTH,
CHARACTER_MAXIMUM_LENGTH
from information_schema.columns
where table_name='t1';
column_name	data_type	CHARACTER_OCTET_LENGTH	CHARACTER_MAXIMUM_LENGTH
f1	blob	4294967295	4294967295
f2	text	4294967295	4294967295
drop table t1;
create table t1(f1 int, f2 int, f3 BIGINT, f4 int,
f5 BIGINT, f6 int, f7 int);
select column_name, NUMERIC_PRECISION, NUMERIC_SCALE
from information_schema.columns
where table_name='t1';
column_name	NUMERIC_PRECISION	NUMERIC_SCALE
f1	10	0
f2	10	0
f3	19	0
f4	10	0
f5	19	0
f6	10	0
f7	10	0
drop table t1;
create table t1 (a int not null, b int);
use information_schema;
select column_name, column_default from columns
where table_schema='test' and table_name='t1';
column_name	column_default
a	NULL
b	NULL
use test;
show columns from t1;
Field	Type	Null	Key	Default	Extra
a	int	NO		NULL	
b	int	YES		NULL	
drop table t1;
alter database information_schema;
ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your Drizzle server version for the right syntax to use near '' at line 1
drop database information_schema;
ERROR 42000: Access denied for user ''@'' to database 'information_schema'
drop table information_schema.tables;
ERROR 42000: Access denied for user ''@'' to database 'information_schema'
alter table information_schema.tables;
ERROR 42000: Access denied for user ''@'' to database 'information_schema'
use information_schema;
create temporary table schemata(f1 char(10));
ERROR 42000: Access denied for user ''@'' to database 'information_schema'
use test;
create table t1(id int);
insert into t1(id) values (1);
select 1 from (select 1 from test.t1) a;
1
1
use information_schema;
select 1 from (select 1 from test.t1) a;
1
1
use test;
drop table t1;
create temporary table t1(f1 int, index(f1));
show columns from t1;
Field	Type	Null	Key	Default	Extra
f1	int	YES	MUL	NULL	
describe t1;
Field	Type	Null	Key	Default	Extra
f1	int	YES	MUL	NULL	
show indexes from t1;
Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment	Index_Comment
t1	1	f1	1	f1	A	0	NULL	NULL	YES	BTREE		
drop table t1;
create table t1(f1 varbinary(32), f2 varbinary(64));
select character_maximum_length, character_octet_length
from information_schema.columns where table_name='t1';
character_maximum_length	character_octet_length
32	32
64	64
drop table t1;
select column_type, group_concat(table_schema, '.', table_name), count(*) as num
from information_schema.columns where
table_schema='information_schema' and
(column_type = 'varchar(7)' or column_type = 'varchar(20)'
 or column_type = 'varchar(27)')
group by column_type order by num;
column_type	group_concat(table_schema, '.', table_name)	num
varchar(20)	information_schema.PLUGINS	1
varchar(27)	information_schema.COLUMNS	1
create table t1(f1 char(1) not null, f2 char(9) not null);
select CHARACTER_MAXIMUM_LENGTH, CHARACTER_OCTET_LENGTH from
information_schema.columns where table_schema='test' and table_name = 't1';
CHARACTER_MAXIMUM_LENGTH	CHARACTER_OCTET_LENGTH
1	4
9	36
drop table t1;
set @a:= '.';
create table t1(f1 char(5));
create table t2(f1 char(5));
select concat(@a, table_name), @a, table_name
from information_schema.tables where table_schema = 'test';
concat(@a, table_name)	@a	table_name
.t1	.	t1
.t2	.	t2
drop table t1,t2;
SELECT t.table_name, c1.column_name
FROM information_schema.tables t
INNER JOIN
information_schema.columns c1
ON t.table_schema = c1.table_schema AND
t.table_name = c1.table_name
WHERE t.table_schema = 'information_schema' AND
c1.ordinal_position =
( SELECT COALESCE(MIN(c2.ordinal_position),1)
FROM information_schema.columns c2
WHERE c2.table_schema = t.table_schema AND
c2.table_name = t.table_name AND
c2.column_name LIKE '%SCHEMA%'
        )
AND t.table_name NOT LIKE 'falcon%';
table_name	column_name
CHARACTER_SETS	CHARACTER_SET_NAME
COLLATIONS	COLLATION_NAME
COLLATION_CHARACTER_SET_APPLICABILITY	COLLATION_NAME
COLUMNS	TABLE_SCHEMA
GLOBAL_STATUS	VARIABLE_NAME
GLOBAL_VARIABLES	VARIABLE_NAME
KEY_COLUMN_USAGE	CONSTRAINT_SCHEMA
PLUGINS	PLUGIN_NAME
PROCESSLIST	ID
REFERENTIAL_CONSTRAINTS	CONSTRAINT_SCHEMA
SCHEMATA	SCHEMA_NAME
SESSION_STATUS	VARIABLE_NAME
SESSION_VARIABLES	VARIABLE_NAME
STATISTICS	TABLE_SCHEMA
TABLES	TABLE_SCHEMA
TABLE_CONSTRAINTS	CONSTRAINT_SCHEMA
INNODB_TRX	trx_id
INNODB_LOCKS	lock_id
INNODB_LOCK_WAITS	requesting_trx_id
INNODB_CMP	page_size
INNODB_CMP_RESET	page_size
INNODB_CMPMEM	page_size
INNODB_CMPMEM_RESET	page_size
SELECT t.table_name, c1.column_name
FROM information_schema.tables t
INNER JOIN
information_schema.columns c1
ON t.table_schema = c1.table_schema AND
t.table_name = c1.table_name
WHERE t.table_schema = 'information_schema' AND
c1.ordinal_position =
( SELECT COALESCE(MIN(c2.ordinal_position),1)
FROM information_schema.columns c2
WHERE c2.table_schema = 'information_schema' AND
c2.table_name = t.table_name AND
c2.column_name LIKE '%SCHEMA%'
        )
AND t.table_name NOT LIKE 'falcon%';
table_name	column_name
CHARACTER_SETS	CHARACTER_SET_NAME
COLLATIONS	COLLATION_NAME
COLLATION_CHARACTER_SET_APPLICABILITY	COLLATION_NAME
COLUMNS	TABLE_SCHEMA
GLOBAL_STATUS	VARIABLE_NAME
GLOBAL_VARIABLES	VARIABLE_NAME
KEY_COLUMN_USAGE	CONSTRAINT_SCHEMA
PLUGINS	PLUGIN_NAME
PROCESSLIST	ID
REFERENTIAL_CONSTRAINTS	CONSTRAINT_SCHEMA
SCHEMATA	SCHEMA_NAME
SESSION_STATUS	VARIABLE_NAME
SESSION_VARIABLES	VARIABLE_NAME
STATISTICS	TABLE_SCHEMA
TABLES	TABLE_SCHEMA
TABLE_CONSTRAINTS	CONSTRAINT_SCHEMA
INNODB_TRX	trx_id
INNODB_LOCKS	lock_id
INNODB_LOCK_WAITS	requesting_trx_id
INNODB_CMP	page_size
INNODB_CMP_RESET	page_size
INNODB_CMPMEM	page_size
INNODB_CMPMEM_RESET	page_size
SELECT MAX(table_name) FROM information_schema.tables;
MAX(table_name)
TABLE_CONSTRAINTS
SELECT table_name from information_schema.tables
WHERE table_name=(SELECT MAX(table_name)
FROM information_schema.tables);
table_name
TABLE_CONSTRAINTS
create table t1 (f1 int);
create table t2 (f1 int, f2 int);
select table_name from information_schema.tables
where table_schema = 'test' and table_name not in
(select table_name from information_schema.columns
where table_schema = 'test' and column_name = 'f3');
table_name
t1
t2
drop table t1,t2;
select 1 as f1 from information_schema.tables  where "CHARACTER_SETS"=
(select cast(table_name as char)  from information_schema.tables
order by table_name limit 1) limit 1;
f1
1
select t.table_name, group_concat(t.table_schema, '.', t.table_name),
count(*) as num1
from information_schema.tables t
inner join information_schema.columns c1
on t.table_schema = c1.table_schema AND t.table_name = c1.table_name
where t.table_schema = 'information_schema' AND
t.table_name not like 'falcon%' AND
c1.ordinal_position =
(select isnull(c2.column_type) -
isnull(group_concat(c2.table_schema, '.', c2.table_name)) +
count(*) as num
from information_schema.columns c2 where
c2.table_schema='information_schema' and
(c2.column_type = 'varchar(7)' or c2.column_type = 'varchar(20)')
group by c2.column_type order by num limit 1)
group by t.table_name order by num1, t.table_name;
table_name	group_concat(t.table_schema, '.', t.table_name)	num1
CHARACTER_SETS	information_schema.CHARACTER_SETS	1
COLLATIONS	information_schema.COLLATIONS	1
COLLATION_CHARACTER_SET_APPLICABILITY	information_schema.COLLATION_CHARACTER_SET_APPLICABILITY	1
COLUMNS	information_schema.COLUMNS	1
GLOBAL_STATUS	information_schema.GLOBAL_STATUS	1
GLOBAL_VARIABLES	information_schema.GLOBAL_VARIABLES	1
INNODB_CMP	information_schema.INNODB_CMP	1
INNODB_CMPMEM	information_schema.INNODB_CMPMEM	1
INNODB_CMPMEM_RESET	information_schema.INNODB_CMPMEM_RESET	1
INNODB_CMP_RESET	information_schema.INNODB_CMP_RESET	1
INNODB_LOCKS	information_schema.INNODB_LOCKS	1
INNODB_LOCK_WAITS	information_schema.INNODB_LOCK_WAITS	1
INNODB_TRX	information_schema.INNODB_TRX	1
KEY_COLUMN_USAGE	information_schema.KEY_COLUMN_USAGE	1
PLUGINS	information_schema.PLUGINS	1
PROCESSLIST	information_schema.PROCESSLIST	1
REFERENTIAL_CONSTRAINTS	information_schema.REFERENTIAL_CONSTRAINTS	1
SCHEMATA	information_schema.SCHEMATA	1
SESSION_STATUS	information_schema.SESSION_STATUS	1
SESSION_VARIABLES	information_schema.SESSION_VARIABLES	1
STATISTICS	information_schema.STATISTICS	1
TABLES	information_schema.TABLES	1
TABLE_CONSTRAINTS	information_schema.TABLE_CONSTRAINTS	1
alter database;
ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your Drizzle server version for the right syntax to use near '' at line 1
alter database test;
ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your Drizzle server version for the right syntax to use near '' at line 1
create table t1 (
f1 varchar(50),
f2 varchar(50) not null,
f3 varchar(50) default '',
f4 varchar(50) default NULL,
f5 bigint not null,
f6 bigint not null default 10,
f7 datetime not null,
f8 datetime default '2006-01-01'
);
select column_default from information_schema.columns where table_name= 't1';
column_default
NULL
NULL

NULL
NULL
10
NULL
2006-01-01 00:00:00
show columns from t1;
Field	Type	Null	Key	Default	Extra
f1	varchar(50)	YES		NULL	
f2	varchar(50)	NO		NULL	
f3	varchar(50)	YES			
f4	varchar(50)	YES		NULL	
f5	bigint	NO		NULL	
f6	bigint	NO		10	
f7	datetime	NO		NULL	
f8	datetime	YES		2006-01-01 00:00:00	
drop table t1;
show fields from information_schema.table_names;
ERROR 42S02: Unknown table 'table_names' in information_schema
show keys from information_schema.table_names;
ERROR 42S02: Unknown table 'table_names' in information_schema
SET max_heap_table_size = DEFAULT;
USE test;
End of 5.0 tests.
SELECT SCHEMA_NAME FROM INFORMATION_SCHEMA.SCHEMATA
WHERE SCHEMA_NAME ='information_schema';
SCHEMA_NAME
information_schema
SELECT TABLE_COLLATION FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_SCHEMA='mysql' and TABLE_NAME= 'db';
TABLE_COLLATION
select * from information_schema.columns where table_schema = NULL;
TABLE_CATALOG	TABLE_SCHEMA	TABLE_NAME	COLUMN_NAME	ORDINAL_POSITION	COLUMN_DEFAULT	IS_NULLABLE	DATA_TYPE	CHARACTER_MAXIMUM_LENGTH	CHARACTER_OCTET_LENGTH	NUMERIC_PRECISION	NUMERIC_SCALE	CHARACTER_SET_NAME	COLLATION_NAME	COLUMN_TYPE	COLUMN_KEY	EXTRA	PRIVILEGES	COLUMN_COMMENT	STORAGE	FORMAT
select * from `information_schema`.`COLUMNS` where `TABLE_NAME` = NULL;
TABLE_CATALOG	TABLE_SCHEMA	TABLE_NAME	COLUMN_NAME	ORDINAL_POSITION	COLUMN_DEFAULT	IS_NULLABLE	DATA_TYPE	CHARACTER_MAXIMUM_LENGTH	CHARACTER_OCTET_LENGTH	NUMERIC_PRECISION	NUMERIC_SCALE	CHARACTER_SET_NAME	COLLATION_NAME	COLUMN_TYPE	COLUMN_KEY	EXTRA	PRIVILEGES	COLUMN_COMMENT	STORAGE	FORMAT
select * from `information_schema`.`KEY_COLUMN_USAGE` where `TABLE_SCHEMA` = NULL;
CONSTRAINT_CATALOG	CONSTRAINT_SCHEMA	CONSTRAINT_NAME	TABLE_CATALOG	TABLE_SCHEMA	TABLE_NAME	COLUMN_NAME	ORDINAL_POSITION	POSITION_IN_UNIQUE_CONSTRAINT	REFERENCED_TABLE_SCHEMA	REFERENCED_TABLE_NAME	REFERENCED_COLUMN_NAME
select * from `information_schema`.`KEY_COLUMN_USAGE` where `TABLE_NAME` = NULL;
CONSTRAINT_CATALOG	CONSTRAINT_SCHEMA	CONSTRAINT_NAME	TABLE_CATALOG	TABLE_SCHEMA	TABLE_NAME	COLUMN_NAME	ORDINAL_POSITION	POSITION_IN_UNIQUE_CONSTRAINT	REFERENCED_TABLE_SCHEMA	REFERENCED_TABLE_NAME	REFERENCED_COLUMN_NAME
select * from `information_schema`.`REFERENTIAL_CONSTRAINTS` where `CONSTRAINT_SCHEMA` = NULL;
CONSTRAINT_CATALOG	CONSTRAINT_SCHEMA	CONSTRAINT_NAME	UNIQUE_CONSTRAINT_CATALOG	UNIQUE_CONSTRAINT_SCHEMA	UNIQUE_CONSTRAINT_NAME	MATCH_OPTION	UPDATE_RULE	DELETE_RULE	TABLE_NAME	REFERENCED_TABLE_NAME
select * from `information_schema`.`REFERENTIAL_CONSTRAINTS` where `TABLE_NAME` = NULL;
CONSTRAINT_CATALOG	CONSTRAINT_SCHEMA	CONSTRAINT_NAME	UNIQUE_CONSTRAINT_CATALOG	UNIQUE_CONSTRAINT_SCHEMA	UNIQUE_CONSTRAINT_NAME	MATCH_OPTION	UPDATE_RULE	DELETE_RULE	TABLE_NAME	REFERENCED_TABLE_NAME
select * from information_schema.schemata where schema_name = NULL;
CATALOG_NAME	SCHEMA_NAME	DEFAULT_CHARACTER_SET_NAME	DEFAULT_COLLATION_NAME	SQL_PATH
select * from `information_schema`.`STATISTICS` where `TABLE_SCHEMA` = NULL;
TABLE_CATALOG	TABLE_SCHEMA	TABLE_NAME	NON_UNIQUE	INDEX_SCHEMA	INDEX_NAME	SEQ_IN_INDEX	COLUMN_NAME	COLLATION	CARDINALITY	SUB_PART	PACKED	NULLABLE	INDEX_TYPE	COMMENT	INDEX_COMMENT
select * from `information_schema`.`STATISTICS` where `TABLE_NAME` = NULL;
TABLE_CATALOG	TABLE_SCHEMA	TABLE_NAME	NON_UNIQUE	INDEX_SCHEMA	INDEX_NAME	SEQ_IN_INDEX	COLUMN_NAME	COLLATION	CARDINALITY	SUB_PART	PACKED	NULLABLE	INDEX_TYPE	COMMENT	INDEX_COMMENT
select * from information_schema.tables where table_schema = NULL;
TABLE_CATALOG	TABLE_SCHEMA	TABLE_NAME	TABLE_TYPE	ENGINE	VERSION	ROW_FORMAT	TABLE_ROWS	AVG_ROW_LENGTH	DATA_LENGTH	MAX_DATA_LENGTH	INDEX_LENGTH	DATA_FREE	AUTO_INCREMENT	CREATE_TIME	UPDATE_TIME	CHECK_TIME	TABLE_COLLATION	CHECKSUM	CREATE_OPTIONS	TABLE_COMMENT
select * from information_schema.tables where table_catalog = NULL;
TABLE_CATALOG	TABLE_SCHEMA	TABLE_NAME	TABLE_TYPE	ENGINE	VERSION	ROW_FORMAT	TABLE_ROWS	AVG_ROW_LENGTH	DATA_LENGTH	MAX_DATA_LENGTH	INDEX_LENGTH	DATA_FREE	AUTO_INCREMENT	CREATE_TIME	UPDATE_TIME	CHECK_TIME	TABLE_COLLATION	CHECKSUM	CREATE_OPTIONS	TABLE_COMMENT
select * from information_schema.tables where table_name = NULL;
TABLE_CATALOG	TABLE_SCHEMA	TABLE_NAME	TABLE_TYPE	ENGINE	VERSION	ROW_FORMAT	TABLE_ROWS	AVG_ROW_LENGTH	DATA_LENGTH	MAX_DATA_LENGTH	INDEX_LENGTH	DATA_FREE	AUTO_INCREMENT	CREATE_TIME	UPDATE_TIME	CHECK_TIME	TABLE_COLLATION	CHECKSUM	CREATE_OPTIONS	TABLE_COMMENT
select * from `information_schema`.`TABLE_CONSTRAINTS` where `TABLE_SCHEMA` = NULL;
CONSTRAINT_CATALOG	CONSTRAINT_SCHEMA	CONSTRAINT_NAME	TABLE_SCHEMA	TABLE_NAME	CONSTRAINT_TYPE
select * from `information_schema`.`TABLE_CONSTRAINTS` where `TABLE_NAME` = NULL;
CONSTRAINT_CATALOG	CONSTRAINT_SCHEMA	CONSTRAINT_NAME	TABLE_SCHEMA	TABLE_NAME	CONSTRAINT_TYPE
#
# Test that the query is visible to self and others.
#
SELECT info FROM information_schema.processlist WHERE id = CONNECTION_ID();
info
SELECT info FROM information_schema.processlist WHERE id = CONNECTION_ID()