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SQL Count 多表总数求和问题

可以这样写: select (select count(*) from bumen)+(select count(*) from mrs) as sum_count 如果两个表结果相同的话,也可以用 select count(*) as sum_count from ( select * from A union all select * from B ) as tmp

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 Qu...

select a. col1, b.col2 from (select count(id) as col1 from table1) as a, (select count(id) as col2 from table2) as b -------------这样写。

可以有两种解决方法, 所需工具:SQL 查询两个count的方法1: SELECT paperName , COUNT (1) AS 总题数 , sum (CASE WHEN statu = 1 THEN 1 ELSE 0 END) AS 审核题数FROM questionGROUP BY paperNme 查询两个count的方法2: select s.总题数, s.审...

select a.栏目,count(b.文章) from sortlist a,article b where a.sortid=b.sortid group by a.栏目;

select tat.id ,tat.name ,count(tbt.id) as numbersd from test_a_temp tat,test_b_temp tbt where tbt.no=tat.id group by tat.id,tat.name order by numbersd desc 其中 test_a_temp 就是你那个A表,test_b_temp 就是B表 A中有两列 ID,NAME ...

select top 10 n.*,d.p from new n, (select count(*) as p,newId from comment group by newId) d where n.newId=@id and n.newId = d.newId order by d.p desc

sum就是求和啊,count是计算 记录的数量, sum只能作用于 是数字的列,是用来计算字段的值的和的, count仅仅是计算记录的条数。

SELECT DB1.A,SUM(DB2.A) as B FROM DB1 LEFT JOIN DB2 ON DB1.B=DB2.B GROUP BY DB1.A 这是没有去重的,看你db1表数据有重复的,假如想去重的话可以加上DISTINCT SELECT DISTINCT DB1.A,SUM(DB2.A) as B FROM DB1 LEFT JOIN DB2 ON DB1.B=DB2.B...

COUNT() 函数返回匹配指定条件的行数。 SQL COUNT(column_name) 语法 COUNT(column_name) 函数返回指定列的值的数目(NULL 不计入): COUNT(*) 函数返回表中的记录数: SELECT COUNT(*) FROM table_name COUNT(DISTINCT column_name) 函数返回...

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