SQL 数据库之一
1. SELECT
实例105
SELECT ID "编号",Name 姓名,
Math_Score '数学成绩', //怎么有的有AS,有的没有
Music_Score AS 音乐成绩,
English_Score AS 英文成绩
from tb_StuScore
SELECT 编号, 商品名称,数量,单价,进价,
(单价*数量) AS 销售额,
(单价*数量-进价*数量) AS 利润
from tb_xsb
SELECT ID,Name,Math_Score,Music_Score,EngLish_Score
from tb_StuScore
WHERE NOT (EngLish_Score>= 90) OR (Math_Score>=95)
SELECT *
from tb_StuScore
WHERE Math_score LIKE '8_'
SELECT *
from tb_StuScore
WHERE Name LIKE '刘%'
SELECT *
from tb_StuScore
WHERE English_score LIKE '9[5-9]%'
SELECT *
from tb_StuScore
WHERE Math_Score LIKE '[^9][0-9]'
SELECT *
from tb_StuScore
WHERE (Name LIKE '刘%')
AND (
(Math_Score LIKE '[^7]_')
OR (EngLish_score LIKE '9[0-9]')
)
SELECT '姓名:'+ Name + ';编号:'+
CONVERT(varchar(3),id) AS 学生信息
from tb_StuScore
SELECT 姓名,LTRIM(姓名) AS 去除左面空格,
RTRIM(姓名) AS 去除右面空格,
LTRIM(RTRIM(姓名)) AS 去除左右空格
from 客户信息表
SELECT *
from tb_StuScore
WHERE Music_Score IN (85,95,100)
SELECT *
from tb_StuScore
WHERE Music_Score NOT IN (85,95,100)
SELECT *
from tb_StuScore
WHERE Music_Score > ALL
( SELECT Music_Score
from tb_StuScore
WHER
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SQL初学者。
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在SQL Server Management Studio中,已经给大家提供了很多常用的现成SQL规范模板。
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1、没试过,网上搜索的
引用
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SELECT … from DEPARTMENT WHERE DEPT_CODE IS NOT NULL;
高效: (索引有效)
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