如何将查询结果转换为案例类? [英] How to convert query result to case class?

问题描述

我正在使用Slick 2.0，并且具有以下User案例类:

I'm using Slick 2.0 and I have the following User case class:

case class User(id: Option[Long], email: String, password: String)

class Users(tag: Tag) extends Table[User](tag, "user") {
  def id = column[Long]("id", O.PrimaryKey, O.AutoInc)
  def email = column[String]("email")
  def password = column[String]("password")

  def * = (id.?, email, password) <> ((User.apply _).tupled, User.unapply _)
}

并且我具有以下功能来通过用户的数据库ID吸引用户:

and I have the following function getting a user via their database id:

def findOneById(id: Long) = DB.withSession { implicit session =>
  val result = (for {
                  u <- users if u.id === id
                } yield (u.id, u.email, u.password)).first
  User(Option(result._1), result._2, result._3)
}

是否有更简单的方法将Seq响应转换回result到User案例类?

Is there an easier way to convert the Seq response back result into the User case class?

推荐答案

好，我找到了答案.我部分来自@benji，部分来自这篇文章:将scala.slick.lifted.Query转换为案例类.

Ok, I found my answer. I got it in part from @benji and in part from this post: Converting scala.slick.lifted.Query to a case class.

以下而不是使用for理解，它返回了Option [User]，这正是我所需要的:

Instead of using a for comprehension, the following returns an Option[User], which is exactly what I need:

def findOneById(id: Long):Option[User] = DB.withSession { implicit session =>
  users.filter(_.id === id).firstOption
}

这篇关于如何将查询结果转换为案例类?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！