在 Slick 中向 joinLeft 添加两个条件

Question

这样编译：

  val table1 = TableQuery[Table1]
  val table2 = TableQuery[Table2]

  val query = for {
    (t1, t2) <- table1 joinLeft table2 on (_.dsType === _.dsType)
  } yield (t1, t2)

这不编译：

  val table1 = TableQuery[Table1]
  val table2 = TableQuery[Table2]

  val query = for {
    (t1, t2) <- table1 joinLeft table2 on (_.dsType === _.dsType && _.dsSk === _.dsSk)
  } yield (t1, t2)

向 joinLeft 添加两个条件的语法是什么？

Answer 1

你可以指定向哪个table请求属性，并用运算符&&分隔：

  val table1 = TableQuery[Table1]
  val table2 = TableQuery[Table2]

    val query = for {
      (t1, t2) <- table1.joinLeft(table2).on((tab1, tab2) => tab1.dsType === tab2.dsType && tab1.dsSk === tab2.dsSk)
    } yield (t1, t2)

与此问题类似的答案是： How to add AND to the join SLICK

在 Slick 中向 joinLeft 添加两个条件

Adding two conditions to joinLeft in Slick

scala

slick

slick-3.0