Question

我正在努力将记录插入postgresql：

val res = DB.withConnection {
        implicit con =>
          SQL(
            """INSERT INTO
              my_table(id, user_id, file_name, added_at)
              VALUES(DEFAULT, {userId}, {fileName}, {currentTime})
              RETURNING id
            """)
            .on("userId" -> 1, "fileName" -> "fileName1", "currentTime" -> new java.sql.Timestamp(DateTime.now.getMillis))
            .executeInsert()
      }

Ok(toJson(JsObject(Seq("res" -> JsString(res.toString)))))

它确实插入了一个值（我可以通过pdAdmin看到），但最终会返回错误ERROR: syntax error at or near "RETURNING"。

如果我删除RETURNING id，则错误将变为TypeDoesNotMatch(Cannot convert requestBody4050249427671619471asTemporaryFile :class java.lang.String to Long for column ColumnName(my_table.file_name,Some(file_name)))]]

当我切断id和DEFAULT时，错误仍然相同。

my_table定义的是

CREATE TABLE my_table
(
  file_name character(255),
  user_id integer,
  added_at timestamp without time zone,
  id serial NOT NULL,
  CONSTRAINT my_table_pk PRIMARY KEY (id),
  CONSTRAINT scan_fk FOREIGN .....
)

为什么？它与file_name有什么关系？

Answer 1

鉴于此表：

CREATE TABLE my_table
(
  file_name character(255),
  user_id integer,
  added_at timestamp without time zone,
  id serial NOT NULL,
  CONSTRAINT my_table_pk PRIMARY KEY (id)
);

您可以插入记录并检索其ID，如下所示：

package dao

import anorm._
import anorm.SqlParser._
import play.api.db.DB
import play.api.Logger
import play.api.Play.current

object MyDAO {

  def insert(fileName: String, userId: Int): Int = {
    val sql = SQL(
      """
        insert into my_table(file_name, user_id, added_at)
        values ({fileName}, {userId}, CURRENT_TIMESTAMP)
        returning id
      """)
      .on(
        "fileName" -> fileName,
        "userId" -> userId)
    DB.withConnection { implicit c =>
      val id = sql.as(scalar[Int].single)
      Logger.info(s"Inserted '$fileName' with id '$id'.")
      id
    }
  }

}

并按照以下方式进行测试：

import org.junit.runner._
import org.specs2.mutable._
import org.specs2.runner._
import play.api.test._
import play.api.test.Helpers._
import dao.MyDAO

@RunWith(classOf[JUnitRunner])
class MyDAOSpec extends Specification {
  "MyDAO" should {
    "insert a record and return its id" in new WithApplication {
      val id = MyDAO.insert("file1", 101)
      id must be_>=(0)
    }
  }
}

有关如何从结果集中检索数据的更多示例，请参阅Anorm, simple SQL data access。

我正在努力从Play中的postgresql中获取id

1 个答案: