本文目录
- sql两张表union all的时候取count,然后进行sum，该怎么实现
- SQL UNION ALL 语句
- sql中 union all 急！！！！
- sql 查询结果合并union all用法_数据库技巧
sql两张表union all的时候取count,然后进行sum，该怎么实现
在最后的地方 随便加个字符， ) a就可以了。缺少一个表名，相当于。
select sum(tmpcount) from ( select count(*) as tmpcount from tab1 union all select count(*) as tmpcount from tab2) a
具体如下：
1、简介
结构化查询语言(Structured Query Language)简称SQL，结构化查询语言是一种数据库查询和程序设计语言，用于存取数据以及查询、更新和管理关系数据库系统;sql 语句就是对数据库进行操作的一种语言。
2、sql语句
更新:update table1 set field1=value1 where 范围
查找:select * from table1 where field1 like ’%value1%’ (所有包含’value1’这个模式的字符串)
排序:select * from table1 order by field1,field2
求和:select sum(field1) as sumvalue from table1
平均:select avg(field1) as avgvalue from table1
最大:select max(field1) as maxvalue from table1
最小:select min(field1) as minvalue from table1
SQL UNION ALL 语句
select convert(varchar(10),rq,120) as ddate,sl,je from kcUNION ALLSELECT ddate + ’月累计’,sl,jeFROM(SELECT kk.ddate,(SELECT SUM(kk2.sl) FROM (SELECT convert(varchar(7),rq,120) as ddate,SUM(sl) AS sl,SUM(je) AS je FROM kcGROUP BY convert(varchar(7),rq,120)) kk2 WHERE kk2.ddate 《= kk.ddate) AS sl,(SELECT SUM(kk3.je) FROM (SELECT convert(varchar(7),rq,120) as ddate,SUM(sl) AS sl,SUM(je) AS je FROM kcGROUP BY convert(varchar(7),rq,120)) kk3 WHERE kk3.ddate 《= kk.ddate) AS jeFROM(SELECT convert(varchar(7),rq,120) as ddate,SUM(sl) AS sl,SUM(je) AS je FROM kcGROUP BY convert(varchar(7),rq,120)) kk) mmunion allselect convert(varchar(7),rq,120)+N’月合计’ as ddate,sum(sl),sum(je) from kcgroup by convert(varchar(7),rq,120)+N’月合计’ORDER BY ddate
sql中 union all 急！！！！
这样写会报错：改为：select *into #table_1from (select * from tab1 union all select * from tab2) as tmp上面建的是临时表sqlserver的这样写：insert into table_1 select *from (select * from tab1 union all select * from tab2) as tmp
sql 查询结果合并union all用法_数据库技巧
复制代码代码如下:--合并重复行select*fromAunionselect*fromB--不合并重复行select*fromAunionallselect*fromB按某个字段排序--合并重复行select*from(select*fromAunionselect*fromB)ASTorderby字段名--不合并重复行select*from(select*fromAunionallselect*fromB)ASTorderby字段名//sqlserver版Select*From(selecttop2id,adddate,title,urlfrombArticlewhereClassId=1orderbyadddatedesc)AUnionAllSelect*From(selecttop2id,adddate,title,urlfrombArticlewhereClassId=2orderbyadddatedesc)BUnionAllSelect*From(selecttop2id,adddate,title,urlfrombArticlewhereClassId=3orderbyadddatedesc)CUnionAllSelect*From(selecttop2id,adddate,title,urlfrombArticlewhereClassId=4orderbyadddatedesc)D//mysql版Select*From(selectid,adddate,title,urlfrombArticlewhereClassId=1orderbyadddatedesclimit0,2)AUnionAllSelect*From(selectid,adddate,title,urlfrombArticlewhereClassId=2orderbyadddatedesclimit0,2)BUnionAllSelect*From(selectid,adddate,title,urlfrombArticlewhereClassId=3orderbyadddatedesclimit0,2)CUnionAllSelect*From(selectid,adddate,title,urlfrombArticlewhereClassId=4orderbyadddatedesclimit0,2)D
