南强小屋 Design By 杰米
复制代码 代码如下:
--合并重复行
select * from A
union
select * from B
--不合并重复行
select * from A
union all
select * from B
按某个字段排序
--合并重复行
select *
from (
select * from A
union
select * from B) AS T
order by 字段名
--不合并重复行
select *
from (
select * from A
union all
select * from B) AS T
order by 字段名
//sql server版
Select * From (
select top 2 id,adddate,title,url from bArticle where ClassId=1 order by adddate desc) A
Union All
Select * From (
select top 2 id,adddate,title,url from bArticle where ClassId=2 order by adddate desc) B
Union All
Select * From (
select top 2 id,adddate,title,url from bArticle where ClassId=3 order by adddate desc) C
Union All
Select * From (
select top 2 id,adddate,title,url from bArticle where ClassId=4 order by adddate desc) D
//mysql版
Select * From (
select id,adddate,title,url from bArticle where ClassId=1 order by adddate desc limit 0,2) A
Union All
Select * From (
select id,adddate,title,url from bArticle where ClassId=2 order by adddate desc limit 0,2) B
Union All
Select * From (
select id,adddate,title,url from bArticle where ClassId=3 order by adddate desc limit 0,2) C
Union All
Select * From (
select id,adddate,title,url from bArticle where ClassId=4 order by adddate desc limit 0,2) D
--合并重复行
select * from A
union
select * from B
--不合并重复行
select * from A
union all
select * from B
按某个字段排序
--合并重复行
select *
from (
select * from A
union
select * from B) AS T
order by 字段名
--不合并重复行
select *
from (
select * from A
union all
select * from B) AS T
order by 字段名
//sql server版
Select * From (
select top 2 id,adddate,title,url from bArticle where ClassId=1 order by adddate desc) A
Union All
Select * From (
select top 2 id,adddate,title,url from bArticle where ClassId=2 order by adddate desc) B
Union All
Select * From (
select top 2 id,adddate,title,url from bArticle where ClassId=3 order by adddate desc) C
Union All
Select * From (
select top 2 id,adddate,title,url from bArticle where ClassId=4 order by adddate desc) D
//mysql版
Select * From (
select id,adddate,title,url from bArticle where ClassId=1 order by adddate desc limit 0,2) A
Union All
Select * From (
select id,adddate,title,url from bArticle where ClassId=2 order by adddate desc limit 0,2) B
Union All
Select * From (
select id,adddate,title,url from bArticle where ClassId=3 order by adddate desc limit 0,2) C
Union All
Select * From (
select id,adddate,title,url from bArticle where ClassId=4 order by adddate desc limit 0,2) D
标签：
sql,合并,union,all
南强小屋 Design By 杰米
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南强小屋 Design By 杰米
暂无sql 查询结果合并union all用法_数据库技巧的评论...
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