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使用SQL语句如何查询一个表中一个字段的值相同,另...

假设表名为table,相同字段为C,不同字段为D select * from table as A ,table as B where A.C=B.C and A.DB.D

可使用如下语句,其中col 为重复值的字段名 select * from t where col in(select col from t as t2 group by col having count(*) > 1); 或 select T.* from T join (select col from T group by col having count(*) > 1) as T2 on T.col= T2...

这个查找过程分两步走: 1、找出这列中有相同内容的记录。代码如下: select 列名 from 表名 group by 列名 having count(列名) > 1 2、把这些有相同内容的记录,查出来。代码如下: select 列名 from 表名 where 列名 in (select 列名 from 表...

查询一个表中某两个字段的相同数据代码是:Select Name,ID From A group by Name,ID having count (*)>1。 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...

-- 先取并集,然后查询student2是否两条(根据id排序)SELECT student FROM (SELECT student FROM A union SELECT student FROM B) a1,A a2 WHERE a2.student=a1.student and (SELECT count(*) FROM B GROUP BY student) >= 2;-- 或者SELECT * FR...

用sql语句查询某表中拥有多个相同字段中的一个值1、对自己的表操作select a.* from hdzx_question a where a.c_id=(select top 1 c_id from hdzx_question where c_title=a.c_title and substring(c_content,0,7000)=substring(a.c_content,0,70...

select * from tb where parent_id not in( select t1.id from tb t1 join tb t2 on t1.id = t2.parent_id )

--把tableA 中sign值为package 赋值给tableB update b set b.sign=a.sign from tableA a,tableB b where a.order_id=b.order_id and a.sign='package' --统计数量 select count(*) as 数量 from tableB where sign='package'

insert into a(name,num,class) values('小米','1001',(select class from b where name = '小米'));

select goods_id,sum(stock) from 表 group by goods_id 要这样? 楼上是在灌水?

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