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drop table if exists t1,t2;
create table t1 (a tinyint not null auto_increment, b blob not null, primary key (a)) type=isam;
delete from t1 where (a & 1);
select sum(length(b)) from t1;
sum(length(b))
3274494
drop table t1;
create table t1 (a int not null auto_increment,b int, primary key (a)) type=isam;
insert into t1 values (1,1),(NULL,2),(3,3),(NULL,4);
delete from t1 where a=4 or a=2;
insert into t1 values (NULL,4),(NULL,5),(6,6);
select * from t1;
a b
1 1
5 5
3 3
4 4
6 6
delete from t1 where a=6;
replace t1 values (3,1);
replace t1 values (3,3);
ALTER TABLE t1 add c int;
insert into t1 values (NULL,6,6);
select * from t1;
a b c
1 1 NULL
5 5 NULL
3 3 NULL
4 4 NULL
6 6 6
drop table t1;
create table t1 (a int,b text, index(a)) type=isam;
Column 'a' is used with UNIQUE or INDEX but is not defined as NOT NULL
create table t1 (a int,b text, index(b)) type=isam;
BLOB column 'b' can't be used in key specification with the used table type
create table t1 (ordid int(8) not null auto_increment, ord varchar(50) not null, primary key (ord,ordid)) type=isam;
Incorrect table definition; There can only be one auto column and it must be defined as a key
create table t1 (ordid int(8), unique (ordid)) type=isam;
Column 'ordid' is used with UNIQUE or INDEX but is not defined as NOT NULL
drop table if exists t1;
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);
create table t2 type=isam select * from t1;
optimize table t1;
Table Op Msg_type Msg_text
test.t1 optimize status OK
check table t1,t2;
Table Op Msg_type Msg_text
test.t1 check status OK
test.t2 check error The handler for the table doesn't support check
repair table t1,t2;
Table Op Msg_type Msg_text
test.t1 repair status OK
test.t2 repair error The handler for the table doesn't support repair
check table t2,t1;
Table Op Msg_type Msg_text
test.t2 check error The handler for the table doesn't support check
test.t1 check status OK
lock tables t1 write;
check table t2,t1;
Table Op Msg_type Msg_text
test.t2 check error Table 't2' was not locked with LOCK TABLES
test.t1 check status OK
show columns from t1;
Field Type Null Key Default Extra
a int(11) PRI 0
b int(11) MUL 0
c int(11) 0
show full columns from t1;
Field Type Null Key Default Extra Privileges Comment
a int(11) PRI 0 select,insert,update,references
b int(11) MUL 0 select,insert,update,references
c int(11) 0 select,insert,update,references
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 4 NULL NULL BTREE
t1 1 b 1 b A 1 NULL NULL BTREE
t1 1 b 2 c A 4 NULL NULL BTREE
drop table t1,t2;
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