MySQL学习笔记7:基本查询
参考表:student
多字段查询
mysql> select id,name,birth from student;
所有字段查询
mysql> select * from student;
where指定查询
mysql> select * from student where id=901; mysql> select * from student where id>=904; mysql> select name from student where department='计算机系';
in指定集合查询
mysql> select * from student where birth in(1988,1990); mysql> select * from student where id in(903,906);
not in非范围查询
mysql> select * from student where birth not in(1990,1998);
between and指定范围查询
mysql> select * from student where birth between 1986 and 1988;
not between and不在指定范围的查询
mysql> select * from student where id not between 904 and 906;
like字符串匹配查询
mysql> select * from student where name like '_三'; mysql> select * from student where name like '张三'; mysql> select * from student where name like '张%';
not like不匹配查询
mysql> select * from student where name not like '张%';
null查询
mysql> select * from student where address is null;
and多条件查询
mysql> select * from student where name like '张%' and birth>1985; mysql> select * from student where name like '张%' and birth>1985 and id like '%3';
or多条件查询
mysql> select * from student where id=905 or birth=1988; mysql> select * from student where id=905 or birth=1988 or sex='女';
distinct查询结果不重复
mysql> select distinct sex from student; mysql> select distinct department from student;
order by查询结果排序
mysql> select * from student order by birth; mysql> select * from student order by birth asc; mysql> select * from student order by birth desc;
group by分组查询
mysql> select sex,group_concat(name) from student group by sex; mysql> select sex,count(name) from student group by sex;
正则表达式查询
mysql> select * from student where birth regexp '1988|1990';
limit限制查询结果数量
mysql> select * from student limit 2; mysql> select * from student limit 1,3;
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