首页 >数据库 >mysql教程 >PHP学习之SQL语句快速入门_MySQL

PHP学习之SQL语句快速入门_MySQL

WBOY
WBOY原创
2016-06-01 13:19:591025浏览

bitsCN.com Select * from tablename
SQL> select * from employees;
Select select list from tablename
SQL> select employee_id,first_name from employees;
Select distinct … from tablename
SQL> select distinct manager_id from employees;
||连接符使用以及 加减乘除以及括号的使用
SQL> select employee_id,first_name||'.'||last_name,salary*(1+0.1)/100,manager_id
2 from employees;
+-做正负号使用
SQL> select -salary from employees;
,>,SQL> select * from employees where salary >13000;
SQL> select * from employees where salary SQL> select * from employees where salary 13000;
SQL> select * from employees where salary =13000;
In
SQL> select -salary from employees where employee_id in (100,101,102);
SQL> select -salary from employees where employee_id in (select employee_id from employees);
not in
SQL> select -salary from employees where employee_id not in (100,101,102);
Any(比任意一个都)
select * from employees where employee_id >any(100,101,102);
some 是 SQL-92 标准的 any 的等效物
select * from employees where employee_id >any(100,101,102);
all(比所有的都)
select * from employees where employee_id >all(100,101,102);
between and
select * from employees where employee_id between 100 and 102;
not between and
select * from employees where employee_id not between 100 and 102;
逻辑操作符
And 和 or
select * from employees where employee_id > 100 and employee_id select * from employees where employee_id > 100 or employee_id Order by
Desc
select * from employees where employee_id between 100 and 102 order by employee_id desc;
Asc
select * from employees where employee_id between 100 and 102 order by employee_id asc;
dual哑元表没有表需要查询的时候可以用它
select sysdate from dual;
select 1*2*3*4*5 from dual;bitsCN.com

声明:
本文内容由网友自发贡献,版权归原作者所有,本站不承担相应法律责任。如您发现有涉嫌抄袭侵权的内容,请联系admin@php.cn