Slick 3.3.3 Filter table using `.inSet` on multiple columns

Question

I have a table with a tuple (2 different columns) as my primary key. I am trying to make a function findByPrimaryKeys(pks: Vector[(Long, Long)]) that returns a query for all the rows with a primary key in the set pks. However, it seems there is no way to do this, I can do

table.filter(t => t.id1.inSet(pks.map(_._1)) && t => t.id2.inSet(pk2.map(_._2)))

However, this is not exactly correct, as it could return something that has a matching id2 but not id1.

Is there way to combine Reps?

Answer 1

Yes, it's possible to combine Rep value, there's an implicit conversion from (Rep[Long], Rep[Long]) to Rep[(Long, Long)]. But that doesn't help in this case because inSet is added through an implicit conversion, and that conversion requires an implicit BaseTypedType[(Long, Long)] to be available, which it isn't.

The only way I know to solve this problem is to use a fold:

table.filter { t =>
  pks.foldLeft[Rep[Boolean]](false) { case (a, (x, y)) =>
    a || (t.id1 === x && t.id2 === y)
  }
}