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drop table if exists t1;
SET NAMES cp1251;
create table t1 (a varchar(10) not null);
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(15) binary, b binary(15));
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;
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