MySql的更新

###MySql的更新

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select* from emp;

 

select * from dept1;

 

#####查询语句

 

 

update emp a,dept b set a.sal=a.sal*b.deptno,b.deptname=a.ename where a.deptno=b.deptno;

 

#####删除记录

 

·delete from emp where ename='dony';

 

#####查询部分字段

 

select ename,hiredate,sal,deptno from emp;

 

#####查询不重复的字段

 

select distinct deptno from emp;

 

 

#####条件查询

 

select * from emp where deptno=1;

 

select * from emp where deptno=1 and sal<3000;