从另一个表向查询添加条件

Question

我有这些表格： rome_sub(id_rome,id_sub)， rome_holland(id_rome,id_holland)

我想做的是做一个像

这样的查询

SELECT * FROM rome_sub where id_sub=X

并加上这个条件：

id_holland IN (Y,Z)

Answer 1

您似乎在寻找EXISTS或IN子句：

select * 
from rome_sub 
where id_sub = 'X'
and id_rome in 
(
  select id_rome 
  from rome_holland 
  where id_holland in ('Y','Z')
);

或者：

select * 
from rome_sub 
where id_sub = 'X'
and exists 
(
  select *
  from rome_holland 
  where id_holland in ('Y','Z')
  and rome_holland.id_rome = rome_sub.id_rome
);

Answer 2

JOIN两个表：

SELECT DISTINCT s.* 
FROM rome_sub AS s
INNER JOIN rome_holland AS h ON s.id_rome = h.id_rome
where s.id_sub = 'X'
  AND h.id_holland IN ('Y', 'Z');