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drop table if exists t1;
CREATE TABLE t1 (id CHAR(12) not null, PRIMARY KEY (id));
insert into t1 values ('000000000001'),('000000000002');
explain select * from t1 where id=000000000001;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index PRIMARY PRIMARY 12 NULL 2 Using where; Using index
select * from t1 where id=000000000001;
id
000000000001
delete from t1 where id=000000000002;
select * from t1;
id
000000000001
drop table t1;
SELECT 'a' = 'a ';
'a' = 'a '
1
SELECT 'a\0' < 'a';
'a\0' < 'a'
1
SELECT 'a\0' < 'a ';
'a\0' < 'a '
1
SELECT 'a\t' < 'a';
'a\t' < 'a'
1
SELECT 'a\t' < 'a ';
'a\t' < 'a '
1
CREATE TABLE t1 (a char(10) not null);
INSERT INTO t1 VALUES ('a'),('a\0'),('a\t'),('a ');
SELECT hex(a),STRCMP(a,'a'), STRCMP(a,'a ') FROM t1;
hex(a) STRCMP(a,'a') STRCMP(a,'a ')
61 0 0
6100 -1 -1
6109 -1 -1
61 0 0
DROP TABLE t1;
SELECT CHAR(31) = '', '' = CHAR(31);
CHAR(31) = '' '' = CHAR(31)
0 0
SELECT CHAR(30) = '', '' = CHAR(30);
CHAR(30) = '' '' = CHAR(30)
0 0
create table t1 (a tinyint(1),b binary(1));
insert into t1 values (0x01,0x01);
select * from t1 where a=b;
a b
Warnings:
Warning 1292 Truncated incorrect DOUBLE value: ''
select * from t1 where a=b and b=0x01;
a b
Warnings:
Warning 1292 Truncated incorrect DOUBLE value: ''
drop table if exists t1;
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