我在Scala中有一个简单的case类，我用一个自动生成的主键（一个序列号）将它Map到DB2表。
Slick显示了生成的SQL，问题似乎是它试图（也）更新主键列，而DB2不允许这样做。
下面是Slick生成的SQL语句：

slick.basic.BasicBackend.action - [update "SOME_THING" set "RECORD_ID" = ?, "STATUS" = ? where "RECORD_ID" = ...]

由于我只是尝试更新STATUS，这就是我想要的（并且应该可以工作）：

slick.basic.BasicBackend.action - [update "SOME_THING" set                  "STATUS" = ? where "RECORD_ID" = ...]

如何修改代码以使UPDATE正常工作？我可以用DELETE+INSERT替换UPDATE，但有更好的方法吗？
使用Slick 3.3.3和Scala 2.12。

import slick.jdbc.DB2Profile.api._
import slick.lifted.ProvenShape

class SomethingTbl(tag: Tag, schemaName: String) extends Table[SomethingRec](tag, _schemaName = Some(schemaName), _tableName = "SOME_THING") {
  def record_id: Rep[Long] = column[Long]("RECORD_ID", O.PrimaryKey, O.AutoInc)

  def status: Rep[String] = column[String]("STATUS")

  override def * : ProvenShape[SomethingRec] = (record_id, status ) <> (SomethingRec.tupled, SomethingRec.unapply)
}

import akka.actor.ActorSystem
import slick.jdbc
import slick.jdbc.DB2Profile
import slick.sql.FixedSqlAction

import scala.concurrent.duration._
import scala.concurrent.{Await, Future}

class SomethingDAO(schemaName: String)(implicit val system: ActorSystem) {

  import slick.jdbc.DB2Profile.api._

  lazy val someThings: TableQuery[SomethingTbl] =
    TableQuery[SomethingTbl](tag => new SomethingTbl(tag, schemaName))

  // Capture the DB-generated sequence number and return it
  private lazy val insertSomething: jdbc.DB2Profile.IntoInsertActionComposer[SomethingRec, SomethingRec] =
    someThings returning someThings.map(_.record_id) into ((rec, record_id) => rec.copy(record_id = record_id))

  private implicit val db: DB2Profile.backend.Database = Database.forConfig("slick-db2")

  def update(e: SomethingRec): Int = {
    val recordFut = db.run(updateSomething(e))
    val record = Await.result(recordFut, Duration.Inf)
    record
  }

  private def updateSomething(e: SomethingRec): FixedSqlAction[Int, NoStream, Effect.Write] = {
    someThings
      .filter(_.record_id === e.record_id)
      .update(e)
      // com.ibm.db2.jcc.am.SqlSyntaxErrorException: DB2 SQL Error: SQLCODE=-798, SQLSTATE=428C9, SQLERRMC=RECORD_ID, DRIVER=4.19.26
  }
}