Using IN operator in SQL

Question

Suppose I have the database consisting of T1 (a, b, c) And I also have the database T2 (a, b, c) Can I use the IN operator to check that there is a record from T1 to T2? Like this for example:

select a
from T1
where (a, b, c) in (select a, b, c
                    from T2)

Or does the IN operator only work on a single value? Thanks for answering :)

question from:https://stackoverflow.com/questions/65891407/using-in-operator-in-sql

Answer 1

Your query can be rewritten using exists

select a
from T1 t1
where exists (select 1
                    from T2 t2 t1.a = t2.a and t1.b = t2.b and t1.c = t2.c)