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|
drop table if exists t1;
select 'a' = 'a', 'a' = 'a ', 'a ' = 'a';
'a' = 'a' 'a' = 'a ' 'a ' = 'a'
1 1 1
select 'a\0' = 'a', 'a\0' < 'a', 'a\0' > 'a';
'a\0' = 'a' 'a\0' < 'a' 'a\0' > 'a'
0 1 0
select 'a' = 'a\0', 'a' < 'a\0', 'a' > 'a\0';
'a' = 'a\0' 'a' < 'a\0' 'a' > 'a\0'
0 0 1
select 'a\0' = 'a ', 'a\0' < 'a ', 'a\0' > 'a ';
'a\0' = 'a ' 'a\0' < 'a ' 'a\0' > 'a '
0 1 0
select 'a ' = 'a\0', 'a ' < 'a\0', 'a ' > 'a\0';
'a ' = 'a\0' 'a ' < 'a\0' 'a ' > 'a\0'
0 0 1
select 'a a' > 'a', 'a \0' < 'a';
'a a' > 'a' 'a \0' < 'a'
1 1
select binary 'a a' > 'a', binary 'a \0' > 'a', binary 'a\0' > 'a';
binary 'a a' > 'a' binary 'a \0' > 'a' binary 'a\0' > 'a'
1 1 1
create table t1 (text1 varchar(32) not NULL, KEY key1 (text1));
insert into t1 values ('teststring'), ('nothing'), ('teststring\t');
check table t1;
Table Op Msg_type Msg_text
test.t1 check status OK
select * from t1 ignore key (key1) where text1='teststring' or
text1 like 'teststring_%' ORDER BY text1;
text1
teststring
teststring
select * from t1 where text1='teststring' or text1 like 'teststring_%';
text1
teststring
teststring
select * from t1 where text1='teststring' or text1 > 'teststring\t';
text1
teststring
select * from t1 order by text1;
text1
nothing
teststring
teststring
explain select * from t1 order by text1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index NULL key1 34 NULL 3 Using index
alter table t1 modify text1 char(32) binary not null;
check table t1;
Table Op Msg_type Msg_text
test.t1 check status OK
select * from t1 ignore key (key1) where text1='teststring' or
text1 like 'teststring_%' ORDER BY text1;
text1
teststring
teststring
select concat('|', text1, '|') as c from t1 where text1='teststring' or text1 like 'teststring_%' order by c;
c
|teststring |
|teststring|
select concat('|', text1, '|') from t1 where text1='teststring' or text1 > 'teststring\t';
concat('|', text1, '|')
|teststring|
select text1, length(text1) from t1 order by text1;
text1 length(text1)
nothing 7
teststring 11
teststring 10
select text1, length(text1) from t1 order by binary text1;
text1 length(text1)
nothing 7
teststring 10
teststring 11
alter table t1 modify text1 blob not null, drop key key1, add key key1 (text1(20));
insert into t1 values ('teststring ');
select concat('|', text1, '|') from t1 order by text1;
concat('|', text1, '|')
|nothing|
|teststring|
|teststring |
|teststring |
select concat('|', text1, '|') from t1 where text1='teststring' or text1 > 'teststring\t';
concat('|', text1, '|')
|teststring|
|teststring |
select concat('|', text1, '|') from t1 where text1='teststring';
concat('|', text1, '|')
|teststring|
select concat('|', text1, '|') from t1 where text1='teststring ';
concat('|', text1, '|')
|teststring |
alter table t1 modify text1 text not null, pack_keys=1;
select concat('|', text1, '|') from t1 where text1='teststring';
concat('|', text1, '|')
|teststring|
|teststring |
select concat('|', text1, '|') from t1 where text1='teststring ';
concat('|', text1, '|')
|teststring|
|teststring |
explain select concat('|', text1, '|') from t1 where text1='teststring ';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref key1 key1 22 const 2 Using where
select concat('|', text1, '|') from t1 where text1 like 'teststring_%';
concat('|', text1, '|')
|teststring |
|teststring |
select concat('|', text1, '|') as c from t1 where text1='teststring' or text1 like 'teststring_%' order by c;
c
|teststring |
|teststring |
|teststring|
select concat('|', text1, '|') from t1 where text1='teststring' or text1 > 'teststring\t';
concat('|', text1, '|')
|teststring|
|teststring |
select concat('|', text1, '|') from t1 order by text1;
concat('|', text1, '|')
|nothing|
|teststring |
|teststring|
|teststring |
drop table t1;
create table t1 (text1 varchar(32) not NULL, KEY key1 (text1)) pack_keys=0;
insert into t1 values ('teststring'), ('nothing'), ('teststring\t');
select concat('|', text1, '|') as c from t1 where text1='teststring' or text1 like 'teststring_%' order by c;
c
|teststring |
|teststring|
select concat('|', text1, '|') from t1 where text1='teststring' or text1 >= 'teststring\t';
concat('|', text1, '|')
|teststring |
|teststring|
drop table t1;
create table t1 (text1 varchar(32) not NULL, KEY key1 using BTREE (text1)) engine=heap;
insert into t1 values ('teststring'), ('nothing'), ('teststring\t');
select * from t1 ignore key (key1) where text1='teststring' or
text1 like 'teststring_%' ORDER BY text1;
text1
teststring
teststring
select * from t1 where text1='teststring' or text1 like 'teststring_%';
text1
teststring
teststring
select * from t1 where text1='teststring' or text1 >= 'teststring\t';
text1
teststring
teststring
select * from t1 order by text1;
text1
nothing
teststring
teststring
explain select * from t1 order by text1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 3 Using filesort
alter table t1 modify text1 char(32) binary not null;
select * from t1 order by text1;
text1
nothing
teststring
teststring
drop table t1;
create table t1 (text1 varchar(32) not NULL, KEY key1 (text1)) engine=innodb;
insert into t1 values ('teststring'), ('nothing'), ('teststring\t');
check table t1;
Table Op Msg_type Msg_text
test.t1 check status OK
select * from t1 where text1='teststring' or text1 like 'teststring_%';
text1
teststring
teststring
select * from t1 where text1='teststring' or text1 > 'teststring\t';
text1
teststring
select * from t1 order by text1;
text1
nothing
teststring
teststring
explain select * from t1 order by text1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index NULL key1 34 NULL 3 Using index
alter table t1 modify text1 char(32) binary not null;
select * from t1 order by text1;
text1
nothing
teststring
teststring
alter table t1 modify text1 blob not null, drop key key1, add key key1 (text1(20));
insert into t1 values ('teststring ');
select concat('|', text1, '|') from t1 order by text1;
concat('|', text1, '|')
|nothing|
|teststring|
|teststring |
|teststring |
alter table t1 modify text1 text not null, pack_keys=1;
select * from t1 where text1 like 'teststring_%';
text1
teststring
teststring
select text1, length(text1) from t1 where text1='teststring' or text1 like 'teststring_%';
text1 length(text1)
teststring 10
teststring 11
teststring 11
select text1, length(text1) from t1 where text1='teststring' or text1 >= 'teststring\t';
text1 length(text1)
teststring 10
teststring 11
teststring 11
select concat('|', text1, '|') from t1 order by text1;
concat('|', text1, '|')
|nothing|
|teststring |
|teststring|
|teststring |
drop table t1;
|
