slick

I want to force slick to create queries like select max(price) from coffees where ... But slick's documentation doesn't help val q = Coffees.map(_.price) //this is query Query[Coffees.type, ...] val q1 = q.min // this is Column[Option[Double]] val q2 = q.max val q3 = q.sum val q4 = q.avg Because those q1-q4 aren't queries, I can't get the results but can use them inside other queries. This statement for { coffee <- Coffees } yield coffee.price.max generates right query but is deprecated (generates warning: " method max in class ColumnExtensionMethods is deprecated: Use Query.max instead"). How

Basically the same question has been asked about a year ago for slick 2.x ( scala slick one-to-many collections ). I'm wondering if there has any progression been made with the release of reactive slick. Let's say for example we have three tables. library , book and library_to_book where a library has many books. What I want is a list of libraries with their books. In scala this would be something like Seq[(Library, Seq[Book])] . The query I have is as follows: val q = (for { l <- libraries ltb <- libraryToBooks if l.id === ltb.libraryId b <- books if ltb.bookId === b.id } yield (l, b) db.run

In the Slick examples there are a few examples of joining where one of the resulting columns can be nulls, as it can be the case when doing left, right, or outer joins. For example: val explicitLeftOuterJoin = for { (c, s) <- Coffees leftJoin Suppliers on (_.supID === _.id) } yield (c.name, s.name.?) But what if I want to return the entire mapped object? What I mean is: val explicitLeftOuterJoin = for { (c, s) <- Coffees leftJoin Suppliers on (_.supID === _.id) } yield (c, s.?) This doesn't seem to work as it complains about "could not find implicit value for evidence parameter of type scala

Is there a way I can neatly do an upsert operation in Slick? The following works but is too obscure/verbose and I need to explicitly state the fields that should be updated: val id = 1 val now = new Timestamp(System.currentTimeMillis) val q = for { u <- Users if u.id === id } yield u.lastSeen q.update(now) match { case 0 => Users.insert((id, now, now)) case _ => Unit } Updated for native upsert/merge support in Slick 2.1 Attention You have to use plain SQL embedding with your database native MERGE statement. All trials to simulate this statement will very likely lead to incorrect results.