sql exists (函数) 是不是存在

sql exists (函数)是否存在select *from A a where exists (select 1from B bwhere b.id a.idand b.name

sql exists (函数) 是否存在

select *  from A a where exists (select 1          from B b         where b.id = a.id           and b.name = 'dennybruce');

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