Suppose I have such schema (simplified), using slick 2.1:
// Banks
case class Bank(id: Int, name: String)
class Banks(tag: Tag) extends Table[Bank](tag, "banks") {
def id = column[Int]("id", O.PrimaryKey)
def name = column[String]("name")
def * = (id, name) <> (Bank.tupled, Bank.unapply)
}
lazy val banks = TableQuery[Banks]
Each bank has, say, 1:1 BankInfo
, which I keep in separate table:
// Bank Info
case class BankInfo(bank_id: Int, ...)
class BankInfos(tag: Tag) extends Table[BankInfo](tag, "bank_infos") {
def bankId = column[Int]("bank_id", O.PrimaryKey)
...
}
lazy val bankInfos = TableQuery[BankInfos]
And each bank has associated 1:M BankItems
:
// Bank Item
case class BankItem(id: Int, bank_id: Int, ...)
class BankItems(tag: Tag) extends Table[BankItem](tag, "bank_items") {
def id = column[Int]("id", O.PrimaryKey)
def bankId = column[Int]("bank_id")
...
}
lazy val bankItems = TableQuery[BankItems]
So, if I used ORM, I would have had convenient accessors for associated data, something like bank.info
or bank.items
. I've read "Migrating from ORMs", and I understand that Slick doesn't support full relation mapping, though I've seen example where foreignKey
was used.
Basically, where should I place my code to access related data (I want to access all BankItems
for some Bank
, and its BankInfo
). Should it be implemented in case class
es, or in Table
classes, or elsewhere? Can someone give me a practical advice on what is a "standard practice" in this case?