Updating table with enum - scala

Question

Trying to insert the information into DB that looks like this:
(UUID, EnumType)
with following logic:
var t = TestTable.query.map(t=> (t.id, t.enumType)) ++= toAdd.map(idTest, enumTest)))
but compiler throws an error for TestTable.query.map(t=> (t.id, t.enumType)) it's interpriting it as type Iteratable[Nothing], am I missing something?
Test table looks like this:
object TestTable {
val query = TableQuery[TestTable]
}
class TestTable(tag: slick.lifted.Tag) extends Table[TestTable](tag, "test_table") {
val id = column[UUID]("id")
val enumType = column[EnumType]("enumType")
override val * = (id, testType) <> (
(TestTable.apply _).tupled,
TestTable.unapply
)

Answer 1

Suppose you have following data structure:
object Color extends Enumeration {
val Blue = Value("Blue")
val Red = Value("Red")
val Green = Value("Green")
}
case class MyType(id: UUID, color: Color.Value)
Define slick schema as following:
class TestTable(tag: slick.lifted.Tag) extends Table[MyType](tag, "test_table") {
val id = column[UUID]("id")
val color = column[Color.Value]("color")
override val * = (id, color) <> ((MyType.apply _).tupled, MyType.unapply)
}
object TestTable {
lazy val query = TableQuery[TestTable]
}
To map enum to SQL data type slick requires implicit MappedColumnType:
implicit val colorTypeColumnMapper: JdbcType[Color.Value] = MappedColumnType.base[Color.Value, String](
e => e.toString,
s => Color.withName(s)
)
Now you can insert values into DB in this way:
val singleInsertAction = TestTable.query += MyType(UUID.randomUUID(), Color.Blue)
val batchInsertAction = TestTable.query ++= Seq(
MyType(UUID.randomUUID(), Color.Blue),
MyType(UUID.randomUUID(), Color.Red),
MyType(UUID.randomUUID(), Color.Green)
)