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drop table if exists t1;
CREATE TABLE t1 (
STRING_DATA char(255) default NULL,
KEY STRING_DATA (STRING_DATA)
) TYPE=MyISAM;
INSERT INTO t1 VALUES ('AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA');
INSERT INTO t1 VALUES ('DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD');
INSERT INTO t1 VALUES ('FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF');
INSERT INTO t1 VALUES ('FGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGG');
INSERT INTO t1 VALUES ('HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH');
INSERT INTO t1 VALUES ('WWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWW');
CHECK TABLE t1;
Table Op Msg_type Msg_text
test.t1 check status OK
drop table t1;
create table t1 (a tinyint not null auto_increment, b blob not null, primary key (a));
check table t1;
Table Op Msg_type Msg_text
test.t1 check status OK
repair table t1;
Table Op Msg_type Msg_text
test.t1 repair status OK
delete from t1 where (a & 1);
check table t1;
Table Op Msg_type Msg_text
test.t1 check status OK
repair table t1;
Table Op Msg_type Msg_text
test.t1 repair status OK
check table t1;
Table Op Msg_type Msg_text
test.t1 check status OK
drop table t1;
create table t1 (a int not null auto_increment, b int not null, primary key (a), index(b));
insert into t1 (b) values (1),(2),(2),(2),(2);
optimize table t1;
Table Op Msg_type Msg_text
test.t1 optimize status OK
show index from t1;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Comment
t1 0 PRIMARY 1 a A 5 NULL NULL
t1 1 b 1 b A 1 NULL NULL
optimize table t1;
Table Op Msg_type Msg_text
test.t1 optimize status Table is already up to date
show index from t1;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Comment
t1 0 PRIMARY 1 a A 5 NULL NULL
t1 1 b 1 b A 1 NULL NULL
drop table t1;
create table t1 (a int not null, b int not null, c int not null, primary key (a),key(b)) type=myisam;
insert into t1 values (3,3,3),(1,1,1),(2,2,2),(4,4,4);
explain select * from t1 order by a;
table type possible_keys key key_len ref rows Extra
t1 ALL NULL NULL NULL NULL 4 Using filesort
explain select * from t1 order by b;
table type possible_keys key key_len ref rows Extra
t1 ALL NULL NULL NULL NULL 4 Using filesort
explain select * from t1 order by c;
table type possible_keys key key_len ref rows Extra
t1 ALL NULL NULL NULL NULL 4 Using filesort
explain select a from t1 order by a;
table type possible_keys key key_len ref rows Extra
t1 index NULL PRIMARY 4 NULL 4 Using index
explain select b from t1 order by b;
table type possible_keys key key_len ref rows Extra
t1 index NULL b 4 NULL 4 Using index
explain select a,b from t1 order by b;
table type possible_keys key key_len ref rows Extra
t1 ALL NULL NULL NULL NULL 4 Using filesort
explain select a,b from t1;
table type possible_keys key key_len ref rows Extra
t1 ALL NULL NULL NULL NULL 4
explain select a,b,c from t1;
table type possible_keys key key_len ref rows Extra
t1 ALL NULL NULL NULL NULL 4
drop table t1;
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