当所有子记录均满足条件时，仅选择父记录

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我有两个表A和B，当所有子项(在表B中)都满足条件时，我只希望父项A的行.如果来自B的一行不符合条件，那么我不需要父A的行.我想我需要在这里使用存在的，但不展示如何使用.

I have two tables A and B where I only want the parent A's rows when all the children (in Table B) meet the criteria. If one row from B does not meet the criteria, then I don't need parent A's row. I think I need to use exists here, but not show how.

以下是数据表:

表A

Primary Key Level 1 low 2 low 3 high 4 high 5 low

表B

Primary Key Phase Parent Primary Key 1 open 1 2 open 1 3 close 1 4 close 2 5 close 2 6 close 3 7 open 4 8 open 4 9 open 5 10 close 5

我正在尝试的查询:

select * from table_a, table_b where table_a.level = 'low' and table_b.phase = 'close' and table_a.primary_key=table_b.parent_primary_key

但是我的查询还会返回table_a.primary_key = 5的行.

but my query would also return rows where the table_a.primary_key = 5.

基本上，我想要返回的唯一行是在table_A.primary_key = 2时，因为该级别较低，并且两个子行的相位都等于关闭.

Basically the only rows I want returned is when table_A.primary_key = 2 beause the level is low, and both children rows have a phase equal to close.

谢谢！

推荐答案

或者:

select a.* from table_a a where a.level = 'low' and 'close' = all (select phase from table_b b where b.parent_primary_key = a.primary_key );