1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
|
drop table if exists t1;
SET NAMES cp1251;
create table t1 (a varchar(10) not null) character set cp1251;
insert into t1 values ("a"),("ab"),("abc");
select * from t1;
a
a
ab
abc
select a, left(a,1) as b from t1;
a b
a a
ab a
abc a
select a, left(a,1) as b from t1 group by a;
a b
a a
ab a
abc a
SELECT DISTINCT RIGHT(a,1) from t1;
RIGHT(a,1)
a
b
c
drop table t1;
create table t1 (a char(3) binary, b binary(3)) character set cp1251;
insert into t1 values ('aaa','bbb'),('AAA','BBB');
select upper(a),upper(b) from t1;
upper(a) upper(b)
AAA bbb
AAA BBB
select lower(a),lower(b) from t1;
lower(a) lower(b)
aaa bbb
aaa BBB
select * from t1 where upper(a)='AAA';
a b
aaa bbb
AAA BBB
select * from t1 where lower(a)='aaa';
a b
aaa bbb
AAA BBB
select * from t1 where upper(b)='BBB';
a b
AAA BBB
select * from t1 where lower(b)='bbb';
a b
aaa bbb
select charset(a), charset(b), charset(binary 'ccc') from t1 limit 1;
charset(a) charset(b) charset(binary 'ccc')
cp1251 binary binary
select collation(a), collation(b), collation(binary 'ccc') from t1 limit 1;
collation(a) collation(b) collation(binary 'ccc')
cp1251_bin binary binary
drop table t1;
create table t1 (
a varchar(16) character set cp1251 collate cp1251_bin not null,
b int(10) default null,
primary key(a)
) charset=cp1251;
insert into t1 (a) values ('air'),
('we'),('g'),('we_toshko'), ('s0urce'),('we_ivo'),('we_iliyan'),
('we_martin'),('vw_grado'),('vw_vasko'),('tn_vili'),('tn_kalina'),
('tn_fakira'),('vw_silvia'),('vw_starshi'),('vw_geo'),('vw_b0x1');
select * from t1 where a like 'we_%';
a b
we_iliyan NULL
we_ivo NULL
we_martin NULL
we_toshko NULL
drop table t1;
|
