SQL Server|第五,六天学习总结
小试身手之 ---SELECT 语句的运用
以tbuserinfo来做讲解
复制整张表格到新表格--备份用到
小试身手之 ---SELECT 语句的运用
以tbuserinfo来做讲解
复制整张表格到新表格--备份用到
[sql]
SELECT *
INTO tbuserinfo2
FROM tbuserinfo
INTO tbuserinfo2
FROM tbuserinfo
//当然,你也可以不整张表的属性复制到新表,只要把* 改为你所需要的列么就可以了,,,
筛选数据范围,后显示
[sql]
//这一段是选择学生年龄10-18的
SELECT *
FROM tbuserinfo
WHERE Stuage BETWEEN 10 AND 18
//这一段是排除年龄10-18之外
SELECT *
FROM tbuserinfo
WHERE Stuage NOT BETWEEN 10 AND 18
SELECT *
FROM tbuserinfo
WHERE Stuage BETWEEN 10 AND 18
//这一段是排除年龄10-18之外
SELECT *
FROM tbuserinfo
WHERE Stuage NOT BETWEEN 10 AND 18
筛选某一字段的属性匹配
[
html]
//筛选某一字段的属性匹配
SELECT *
FROM tbuserinfo
WHERE Stuage IN(10 ,18 )
SELECT *
FROM tbuserinfo
WHERE Stuage IN(10 ,18 )
用条件表达式来筛选
[sql]
//用条件判断表达式筛选
SELECT *
FROM tbuserinfo
WHERE Stuage > 10 AND Stuage < 15
//有时候很多复杂的选择,都是由AND 和 OR一起组合而成的
SELECT *
FROM tbuserinfo
WHERE Stuage > 25 OR(Stunum > 2 AND Stuage < 15 )
SELECT *
FROM tbuserinfo
//有时候很多复杂的选择,都是由AND 和 OR一起组合而成的
SELECT *
FROM tbuserinfo
WHERE Stuage > 25 OR(Stunum > 2 AND Stuage < 15 )
模糊查询搜索
%1%(%字符%) :%匹配0个或者多个字符段 ,比如55511,011,51,1都会被筛选到
_1_(_字符_): 单个字符匹配 ,比如 11,10,31
[sql]
SELECT *
FROM tbuserinfo
WHERE Stuage LIKE '%1%'
SELECT *
FROM tbuserinfo
WHERE Stuage LIKE '1_'
FROM tbuserinfo
WHERE Stuage LIKE '%1%'
SELECT *
FROM tbuserinfo
WHERE Stuage LIKE '1_'
\
更新某个字段的数据
[sql]
UPDATE tbuserinfo
SET Stuage = 18
WHERE Stunum > 10
SET Stuage = 18
WHERE Stunum > 10
