需要使用多个“ AND”转换OUTER JOIN

Question

I have this raw sql I'd like to convert to Esqueleto. It should bring all the group s that user ID 1, isn't registered to via the group_membership table.

SELECT * 
FROM group
LEFT OUTER JOIN group_membership
  ON (group.id = group_membership.group_id AND group_membership.user_id=1)
  WHERE group_membership.group_id IS NULL

Answer 1

And here is the answer I gathered from different issues:

getGroups userId = do
    runDB
        . E.select
        . E.from $ \(group `E.LeftOuterJoin` groupMembership) -> do
            E.on $ E.just (group ^. GroupId) E.==. (groupMembership ?. GroupMembershipGroupId) &&.
                   (groupMembership ?. GroupMembershipUserId) E.==. E.just (E.val userId)
            E.where_ $ E.isNothing (groupMembership ?. GroupMembershipGroupId)
            return
              ( group ^. GroupId
              , group ^. GroupTitle
              )