SQL to select distinct values from table with foreign key -


i have 2 tables: a (a_id int, string fields...) , b (b_id, string field "name" , referenced column a_id).
want select unique values table a b.name like "%somestring%".

you use exists:

select a.* tablea exists (    select 1 tableb b     a.a_id = b.a_id     ,  b.name "%somestring%" )

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