SQL基础语句
-------------------------------------------------------
【1】分组查询
SELECT*FROM emp ORDER BY deptno;
【2】内联语句
SELECT m.*,d.*FROM emp m INNER
JOIN dept d on m.deptno=d.deptno
SELECT * FROM emp e INNER JOIN dept d on e.deptno=d.deptno
【3】分组、内联结合
SELECT xin.*,d.dname,d.loc from
(SELECT deptno,sum(sal),COUNT(empno) from emp group by deptno) xin
INNER JOIN dept d on xin.deptno=d.deptno;
SELECT emp.deptno,dept.dname from emp INNER JOIN dept ON emp.deptno=dept.deptno GROUP BY emp.deptno;
[4] having between and语法
SELECT deptno,count(empno),sum(sal) for emp GROUP BY deptno HAVING avg_sal>2000 and sal<5000
BETWEEN 200 and 2500
[5]link语法 分页
SELECT * from emp ORDER BY sal LIMIT 1,2
效果图