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
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
|
drop table if exists t1,t2;
create table t1 (name char(20) not null, primary key (name));
create table t2 (name char(20) binary not null, primary key (name));
insert into t1 values ("å");
insert into t1 values ("ä");
insert into t1 values ("ö");
insert into t2 select * from t1;
select * from t1 order by name;
name
å
ä
ö
select concat("*",name,"*") from t1 order by 1;
concat("*",name,"*")
*å*
*ä*
*ö*
select min(name),min(concat("*",name,"*")),max(name),max(concat("*",name,"*")) from t1;
min(name) min(concat("*",name,"*")) max(name) max(concat("*",name,"*"))
å *å* ö *ö*
select * from t2 order by name;
name
ä
å
ö
select concat("*",name,"*") from t2 order by 1;
concat("*",name,"*")
*ä*
*å*
*ö*
select min(name),min(concat("*",name,"*")),max(name),max(concat("*",name,"*")) from t2;
min(name) min(concat("*",name,"*")) max(name) max(concat("*",name,"*"))
ä *ä* ö *ö*
select name from t1 where name between 'Ä' and 'Ö';
name
ä
ö
select name from t2 where name between 'ä' and 'ö';
name
ä
å
ö
select name from t2 where name between 'Ä' and 'Ö';
name
drop table t1,t2;
create table t1 (a char(10) not null, b char(10) binary not null,key (a), key(b));
insert into t1 values ("hello ","hello "),("hello2 ","hello2 ");
select concat("-",a,"-",b,"-") from t1 where a="hello";
concat("-",a,"-",b,"-")
-hello-hello-
select concat("-",a,"-",b,"-") from t1 where a="hello ";
concat("-",a,"-",b,"-")
-hello-hello-
select concat("-",a,"-",b,"-") from t1 ignore index (a) where a="hello ";
concat("-",a,"-",b,"-")
-hello-hello-
select concat("-",a,"-",b,"-") from t1 where b="hello";
concat("-",a,"-",b,"-")
-hello-hello-
select concat("-",a,"-",b,"-") from t1 where b="hello ";
concat("-",a,"-",b,"-")
-hello-hello-
select concat("-",a,"-",b,"-") from t1 ignore index (b) where b="hello ";
concat("-",a,"-",b,"-")
-hello-hello-
alter table t1 modify b tinytext not null, drop key b, add key (b(100));
select concat("-",a,"-",b,"-") from t1;
concat("-",a,"-",b,"-")
-hello-hello-
-hello2-hello2-
select concat("-",a,"-",b,"-") from t1 where b="hello ";
concat("-",a,"-",b,"-")
-hello-hello-
select concat("-",a,"-",b,"-") from t1 ignore index (b) where b="hello ";
concat("-",a,"-",b,"-")
-hello-hello-
drop table t1;
create table t1 (b char(8));
insert into t1 values(NULL);
select b from t1 where binary b like '';
b
select b from t1 group by binary b like '';
b
NULL
select b from t1 having binary b like '';
b
drop table t1;
create table t1 (a char(3) binary, b binary(3));
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')
latin1 binary binary
select collation(a), collation(b), collation(binary 'ccc') from t1 limit 1;
collation(a) collation(b) collation(binary 'ccc')
latin1_bin binary binary
drop table t1;
create table t1( firstname char(20), lastname char(20));
insert into t1 values ("john","doe"),("John","Doe");
select * from t1 where firstname='john' and firstname like binary 'john';
firstname lastname
john doe
select * from t1 where firstname='john' and binary 'john' = firstname;
firstname lastname
john doe
select * from t1 where firstname='john' and firstname = binary 'john';
firstname lastname
john doe
select * from t1 where firstname='John' and firstname like binary 'john';
firstname lastname
john doe
select * from t1 where firstname='john' and firstname like binary 'John';
firstname lastname
John Doe
drop table t1;
create table t1 (a binary);
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` binary(1) DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
drop table t1;
create table t1 (col1 binary(4));
insert into t1 values ('a'),('a ');
select hex(col1) from t1;
hex(col1)
61000000
61200000
alter table t1 modify col1 binary(10);
select hex(col1) from t1;
hex(col1)
61000000000000000000
61200000000000000000
insert into t1 values ('b'),('b ');
select hex(col1) from t1;
hex(col1)
61000000000000000000
61200000000000000000
62000000000000000000
62200000000000000000
drop table t1;
CREATE TABLE t1 (
a binary(20) NOT NULL DEFAULT '\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0',
index idx(a)
);
INSERT INTO t1 SET a=unhex('1F9480179366F2BF567E1C4B964C1EF029087575');
INSERT INTO t1 SET a=unhex('1F9480179366F2BF567E1C4B964C1EF029082020');
INSERT INTO t1 SET a=unhex('1F9480179366F2BF567E1C4B964C1EF029080707');
SELECT hex(a) FROM t1 order by a;
hex(a)
1F9480179366F2BF567E1C4B964C1EF029080707
1F9480179366F2BF567E1C4B964C1EF029082020
1F9480179366F2BF567E1C4B964C1EF029087575
EXPLAIN SELECT hex(a) FROM t1 order by a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index NULL idx 20 NULL 3 Using index
SELECT hex(a) from t1 WHERE a=unhex('1F9480179366F2BF567E1C4B964C1EF029082020');
hex(a)
1F9480179366F2BF567E1C4B964C1EF029082020
EXPLAIN
SELECT hex(a) from t1 WHERE a=unhex('1F9480179366F2BF567E1C4B964C1EF029082020');
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref idx idx 20 const 1 Using where; Using index
SELECT hex(a) from t1 WHERE a=unhex('1F9480179366F2BF567E1C4B964C1EF02908');
hex(a)
DROP TABLE t1;
CREATE TABLE t1 (
id numeric(20) NOT NULL,
lang varchar(8) NOT NULL,
msg varchar(32) NOT NULL,
PRIMARY KEY (id,lang)
);
INSERT INTO t1 VALUES (33, 'en', 'zzzzzzz');
INSERT INTO t1 VALUES (31, 'en', 'xxxxxxx');
INSERT INTO t1 VALUES (32, 'en', 'yyyyyyy');
SELECT * FROM t1 WHERE id=32;
id lang msg
32 en yyyyyyy
DROP TABLE t1;
|
