scala - Do Aggregation with Slick -


my database structure looks this:

id | content

i entry max id (not id).

i read answer how make aggregations slick, found there no first method in statement: query(coffees.map(_.price).max).first. how now?

what if need content of item max id?

to retrieve column, following. below example calculates max of 1 column, finds row maximum value, , returns value of column in row:

val coffees = tablequery[coffees]  val mostexpensivecoffeequery =   {     maxprice <- coffees.map(_.price).max.result     c <- maxprice match {       case some(p) => coffees.filter(_.price === p).result       case none => dbio.successful(seq())     }   } yield c.headoption.map(_.name)  val mostexpensivecoffee = db.run(mostexpensivecoffeequery) // future[option[string]]

alternatively, return full coffees object:

val mostexpensivecoffeequery =   {     ...   } yield c.headoption  val mostexpensivecoffee = db.run(mostexpensivecoffeequery) // future[option[coffees]]

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