How to make aggregations with slick

Question

I want to force slick to create queries like

select max(price) from coffees where ... 

But slick\'s documentation doesn\'t help

Answer 1

As far as I can tell is the first one simply

Query(Coffees.map(_.price).max).first

And the second one

val maxQuery = Coffees
  .groupBy { _.name }
  .map { case (name, c) =>
    name -> c.map(_.price).max
  }

maxQuery.list

or

val maxQuery = for {
  (name, c) <- Coffees groupBy (_.name)
} yield name -> c.map(_.price).max

maxQuery.list