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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 ("�");
insert into t1 values ("�");
insert into t1 values ("�");
insert into t2 select * from t1;
select * from t1 order by name;
name
�
�
�
select concat("*",name,"*") from t1 order by 1;
concat("*",name,"*")
*�*
*�*
*�*
select min(name),min(concat("*",name,"*")),max(name),max(concat("*",name,"*")) from t1;
min(name) min(concat("*",name,"*")) max(name) max(concat("*",name,"*"))
� *�* � *�*
select * from t2 order by name;
name
�
�
�
select concat("*",name,"*") from t2 order by 1;
concat("*",name,"*")
*�*
*�*
*�*
select min(name),min(concat("*",name,"*")),max(name),max(concat("*",name,"*")) from t2;
min(name) min(concat("*",name,"*")) max(name) max(concat("*",name,"*"))
� *�* � *�*
select name from t1 where name between '�' and '�';
name
�
�
select name from t2 where name between '�' and '�';
name
�
�
�
select name from t2 where name between '�' and '�';
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;
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