问题描述

想要将 MySQL INT 位掩码映射到 Slick.

Want to map MySQL INT bitmask to Slick.

我找到了这个，但是如何使用它没有什么问题

I've found this but have little problem how to use it

https://github.com/nafg/slick-additions/blob/master/src/main/scala/scala/slick/additions/Enum.scala

任何帮助我应该如何定义对象，即

Any help how should I define object for i.e.

mysql 列 INT(3) 带有包含 3 个值的 Enum:让我们在此处将它们命名为 a、b、c.

mysql column INT(3) with Enum containing 3 values: lets name them a,b,c here.

推荐答案

我通过以下方式解决了 Enums 的问题(以您的值为例):

I solved the problem with Enums in the following way (taking your values for an example):

import play.api.db.slick.DB
import play.api.db.slick.Config.driver.simple._


sealed trait MyEnum
case object MyEnumA extends MyEnum
case object MyEnumB extends MyEnum
case object MyEnumC extends MyEnum

object MyEnumMapper {
  val string_enum_mapping:Map[String,MyEnum] = Map(
     "a" -> MyEnumA,
     "b" -> MyEnumB,
     "c" -> MyEnumC
  )
  val enum_string_mapping:Map[MyEnum,String] = string_enum_mapping.map(_.swap)
  implicit val myEnumStringMapper = MappedTypeMapper.base[MyEnum,String](
    e => enum_string_mapping(e),
    s => string_enum_mapping(s)
  )
}

import MyEnumMapper._

case class MyData(
 ......
 enumValue: MyEnum,
 .....
)

................

object MyDataTable extends Table[MyData]("<table_name>") {
......
def enumValue = column[MyEnum]("<field_name>")
.....

.... /* whatever lifted or direct slick calls you want */ 

}

如果在 Play 2.1 和 Play 2.2、Slick 1.0.0 和 MariaDB 5.5(与 MySQL 相同)中都对我有用

If works for me in both Play 2.1 and Play 2.2, Slick 1.0.0 and MariaDB 5.5 (same as MySQL)

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