下面是两个要联接的表,第一个是media_taxonomy,第二个是media_taxonomy_map
media_taxonomy:
media_taxonomy_map:
这是我的SQL查询
select * from media_taxonomy_map as mtm
join media_taxonomy as mt
on mtm.media_taxonomy_id = mt.media_taxonomy_id
但是,我还希望media_taxonomy_map表中media_taxonomy_id为0的联接表中的行
这可能吗?
答案 0 :(得分:2)
我猜您要在表中所有行。如果是这样,只需使用left join
:
select *
from media_taxonomy_map as mtm left join
media_taxonomy as mt
on mtm.media_taxonomy_id = mt.media_taxonomy_id;
如果您特别想要匹配项或0
,则可以过滤:
select *
from media_taxonomy_map as mtm left join
media_taxonomy as mt
on mtm.media_taxonomy_id = mt.media_taxonomy_id
where mtm.media_taxonomy_id = 0 or mt.media_taxonomy_id is not null;