php - mySQL SELECT AS for multiple criteria -


i need combine these 2 queries 1:

select user1id friendid friends user2id = '$userid' union select user2id friendid friends user1id = '$userid'

then

select firstname, lastname users id = friendid (that established)

i guess mysql's union (manual) keyword looking for.

edit due edited question:

you need subquery trying (a join might work, more complicated):

select firstname, lastname users id in (     select user1id friendid friends user2id = '$userid'     union     select user2id friendid friends user1id = '$userid' )

note subqueries can cause performance issues in large tables and/or complicated queries. may want refactor subquery join in case.


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