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drop table if exists t1,t2;
create table t1 (a int not null primary key, b int not null,c int not null, key(b,c));
insert into t1 values (1,2,2),(2,2,3),(3,2,4),(4,2,4);
check table t1 fast;
Table Op Msg_type Msg_text
test.t1 check status Table is already up to date
check table t1 fast;
Table Op Msg_type Msg_text
test.t1 check status Table is already up to date
check table t1 changed;
Table Op Msg_type Msg_text
test.t1 check status OK
insert into t1 values (5,5,5);
check table t1 changed;
Table Op Msg_type Msg_text
test.t1 check status OK
check table t1 medium;
Table Op Msg_type Msg_text
test.t1 check status OK
check table t1 extended;
Table Op Msg_type Msg_text
test.t1 check status OK
show index from t1;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment
t1 0 PRIMARY 1 a A 5 NULL NULL BTREE
t1 1 b 1 b A 1 NULL NULL BTREE
t1 1 b 2 c A 5 NULL NULL BTREE
insert into t1 values (5,5,5);
Duplicate entry '5' for key 1
optimize table t1;
Table Op Msg_type Msg_text
test.t1 optimize status OK
optimize table t1;
Table Op Msg_type Msg_text
test.t1 optimize status Table is already up to date
drop table t1;
show variables like "wait_timeout%";
Variable_name Value
wait_timeout 28800
show variables like "WAIT_timeout%";
Variable_name Value
wait_timeout 28800
show variables like "this_doesn't_exists%";
Variable_name Value
show table status from test like "this_doesn't_exists%";
Name Type Row_format Rows Avg_row_length Data_length Max_data_length Index_length Data_free Auto_increment Create_time Update_time Check_time Charset Create_options Comment
show databases;
Database
mysql
test
show databases like "test%";
Database (test%)
test
create table t1 (f1 int not null, f2 int not null, f3 int not null, f4 int not null, primary key(f1,f2,f3,f4));
insert into t1 values (1,1,1,0),(1,1,2,0),(1,1,3,0),(1,2,1,0),(1,2,2,0),(1,2,3,0),(1,3,1,0),(1,3,2,0),(1,3,3,0),(1,1,1,1),(1,1,2,1),(1,1,3,1),(1,2,1,1),(1,2,2,1),(1,2,3,1),(1,3,1,1),(1,3,2,1),(1,3,3,1);
analyze table t1;
Table Op Msg_type Msg_text
test.t1 analyze status OK
show index from t1;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment
t1 0 PRIMARY 1 f1 A 1 NULL NULL BTREE
t1 0 PRIMARY 2 f2 A 3 NULL NULL BTREE
t1 0 PRIMARY 3 f3 A 9 NULL NULL BTREE
t1 0 PRIMARY 4 f4 A 18 NULL NULL BTREE
repair table t1;
Table Op Msg_type Msg_text
test.t1 repair status OK
show index from t1;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment
t1 0 PRIMARY 1 f1 A 1 NULL NULL BTREE
t1 0 PRIMARY 2 f2 A 3 NULL NULL BTREE
t1 0 PRIMARY 3 f3 A 9 NULL NULL BTREE
t1 0 PRIMARY 4 f4 A 18 NULL NULL BTREE
drop table t1;
create temporary table t1 (a int not null);
show create table t1;
Table Create Table
t1 CREATE TEMPORARY TABLE `t1` (
`a` int(11) NOT NULL default '0'
) TYPE=MyISAM CHARSET=latin1
alter table t1 rename t2;
show create table t2;
Table Create Table
t2 CREATE TEMPORARY TABLE `t2` (
`a` int(11) NOT NULL default '0'
) TYPE=MyISAM CHARSET=latin1
drop table t2;
create table t1 (
test_set set( 'val1', 'val2', 'val3' ) not null default '',
name char(20) default 'O''Brien' comment 'O''Brien as default',
c int not null comment 'int column'
) comment = 'it\'s a table' ;
show create table t1 ;
Table Create Table
t1 CREATE TABLE `t1` (
`test_set` set('val1','val2','val3') NOT NULL default '',
`name` char(20) character set latin1 default 'O''Brien' COMMENT 'O''Brien as default',
`c` int(11) NOT NULL default '0' COMMENT 'int column'
) TYPE=MyISAM CHARSET=latin1 COMMENT='it''s a table'
show full columns from t1;
Field Type Null Key Default Extra Privileges Comment
test_set set('val1','val2','val3') select,insert,update,references
name char(20) character set latin1 YES O'Brien select,insert,update,references O'Brien as default
c int(11) 0 select,insert,update,references int column
drop table t1;
create table t1 (a int not null, unique aa (a));
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` int(11) NOT NULL default '0',
UNIQUE KEY `aa` (`a`)
) TYPE=MyISAM CHARSET=latin1
drop table t1;
create table t1 (a int not null, primary key (a));
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` int(11) NOT NULL default '0',
PRIMARY KEY (`a`)
) TYPE=MyISAM CHARSET=latin1
drop table t1;
flush tables;
show open tables;
Database Table In_use Name_locked
create table t1(n int);
insert into t1 values (1);
show open tables;
Database Table In_use Name_locked
test t1 0 0
drop table t1;
create table t1 (a int not null, b VARCHAR(10), INDEX (b) ) AVG_ROW_LENGTH=10 CHECKSUM=1 COMMENT="test" TYPE=MYISAM MIN_ROWS=10 MAX_ROWS=100 PACK_KEYS=1 DELAY_KEY_WRITE=1 ROW_FORMAT=fixed;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` int(11) NOT NULL default '0',
`b` char(10) character set latin1 default NULL,
KEY `b` (`b`)
) TYPE=MyISAM CHARSET=latin1 MIN_ROWS=10 MAX_ROWS=100 AVG_ROW_LENGTH=10 PACK_KEYS=1 CHECKSUM=1 DELAY_KEY_WRITE=1 ROW_FORMAT=FIXED COMMENT='test'
alter table t1 MAX_ROWS=200 ROW_FORMAT=dynamic PACK_KEYS=0;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` int(11) NOT NULL default '0',
`b` varchar(10) character set latin1 default NULL,
KEY `b` (`b`)
) TYPE=MyISAM CHARSET=latin1 MIN_ROWS=10 MAX_ROWS=200 AVG_ROW_LENGTH=10 PACK_KEYS=0 CHECKSUM=1 DELAY_KEY_WRITE=1 ROW_FORMAT=DYNAMIC COMMENT='test'
ALTER TABLE t1 AVG_ROW_LENGTH=0 CHECKSUM=0 COMMENT="" MIN_ROWS=0 MAX_ROWS=0 PACK_KEYS=DEFAULT DELAY_KEY_WRITE=0 ROW_FORMAT=default;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` int(11) NOT NULL default '0',
`b` varchar(10) character set latin1 default NULL,
KEY `b` (`b`)
) TYPE=MyISAM CHARSET=latin1
drop table t1;
create table t1 (a decimal(9,2), b decimal (9,0), e double(9,2), f double(5,0), h float(3,2), i float(3,0));
show columns from t1;
Field Type Null Key Default Extra
a decimal(9,2) YES NULL
b decimal(9,0) YES NULL
e double(9,2) YES NULL
f double(5,0) YES NULL
h float(3,2) YES NULL
i float(3,0) YES NULL
show full columns from t1;
Field Type Null Key Default Extra Privileges Comment
a decimal(9,2) YES NULL select,insert,update,references
b decimal(9,0) YES NULL select,insert,update,references
e double(9,2) YES NULL select,insert,update,references
f double(5,0) YES NULL select,insert,update,references
h float(3,2) YES NULL select,insert,update,references
i float(3,0) YES NULL select,insert,update,references
drop table t1;
create table t1 (c decimal, d double, f float, r real);
show columns from t1;
Field Type Null Key Default Extra
c decimal(10,0) YES NULL
d double YES NULL
f float YES NULL
r double YES NULL
drop table t1;
create table t1 (c decimal(3,3), d double(3,3), f float(3,3));
show columns from t1;
Field Type Null Key Default Extra
c decimal(4,3) YES NULL
d double(4,3) YES NULL
f float(4,3) YES NULL
drop table t1;
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