Using Auto Incrementing fields with PostgreSQL and Slick

Question

How does one insert records into PostgreSQL using AutoInc keys with Slick mapped tables? If I use and Option for the id in my case class and set it to None, then PostgreSQL will complain on insert that the field cannot be null. This works for H2, but not for PostgreSQL:

//import scala.slick.driver.H2Driver.simple._ //import scala.slick.driver.BasicProfile.SimpleQL.Table import scala.slick.driver.PostgresDriver.simple._ import Database.threadLocalSession  object TestMappedTable extends App{      case class User(id: Option[Int], first: String, last: String)      object Users extends Table[User]("users") {         def id = column[Int]("id", O.PrimaryKey, O.AutoInc)         def first = column[String]("first")         def last = column[String]("last")         def * = id.? ~ first ~ last <> (User, User.unapply _)         def ins1 = first ~ last returning id         val findByID = createFinderBy(_.id)         def autoInc = id.? ~ first ~ last <> (User, User.unapply _) returning id     }   // implicit val session = Database.forURL("jdbc:h2:mem:test1", driver = "org.h2.Driver").createSession()     implicit val session = Database.forURL("jdbc:postgresql:test:slicktest",                            driver="org.postgresql.Driver",                            user="postgres",                            password="xxx")    session.withTransaction{     Users.ddl.create      // insert data     print(Users.insert(User(None, "Jack", "Green" )))     print(Users.insert(User(None, "Joe", "Blue" )))     print(Users.insert(User(None, "John", "Purple" )))     val u = Users.insert(User(None, "Jim", "Yellow" ))   //  println(u.id.get)     print(Users.autoInc.insert(User(None, "Johnathan", "Seagul" )))   }   session.withTransaction{     val queryUsers = for {     user <- Users   } yield (user.id, user.first)   println(queryUsers.list)    Users.where(_.id between(1, 2)).foreach(println)   println("ID 3 -> " + Users.findByID.first(3))   } } 

Using the above with H2 succeeds, but if I comment it out and change to PostgreSQL, then I get:

[error] (run-main) org.postgresql.util.PSQLException: ERROR: null value in column "id" violates not-null constraint org.postgresql.util.PSQLException: ERROR: null value in column "id" violates not-null constraint 

Answer 1

This is working here:

object Application extends Table[(Long, String)]("application") {        def idlApplication = column[Long]("idlapplication", O.PrimaryKey, O.AutoInc)     def appName = column[String]("appname")     def * = idlApplication ~ appName     def autoInc = appName returning idlApplication }  var id = Application.autoInc.insert("App1") 

This is how my SQL looks:

CREATE TABLE application (idlapplication BIGSERIAL PRIMARY KEY, appName VARCHAR(500)); 

Update:

The specific problem with regard to a mapped table with User (as in the question) can be solved as follows:

  def forInsert = first ~ last <>     ({ (f, l) => User(None, f, l) }, { u:User => Some((u.first, u.last)) }) 

This is from the test cases in the Slick git repository.