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MySQL数据库 - 单表查询(二)
2022-04-23 19:28:00 【x 心 动】
第1关:带 LIKE 的字符匹配查询
USE Company;
######### Begin #########
select Name ,Salary
from tb_emp
where Name like 'C%';
######### End #########
第2关:查询空值与去除重复结果
USE Company;
######### Begin #########
select *
from tb_emp
where DeptId IS NULL;
######### End #########
######### Begin #########
select distinct Name
from tb_emp;
######### End #########
第3关:带 AND 与 OR 的多条件查询
USE Company;
######### Begin #########
select *
from tb_emp
where DeptId='301' and Salary>3000;
######### End #########
######### Begin #########
select *
from tb_emp
where DeptId='301' OR DeptId='303';
######### End #########
版权声明
本文为[x 心 动]所创,转载请带上原文链接,感谢
https://blog.csdn.net/qq_45623072/article/details/124055761
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