如何在Doobie中读/写时间戳(Postgres)

import doobie._
import doobie.implicits._
import doobie.util.ExecutionContexts
import cats.effect.IO
import java.util.Date

object Main extends App {
  // Step 1: Define case class to hold the result
  case class TimestampData(id: Int, timestamp: Date)

  // Step 2: Create a database connection pool
  implicit val cs = IO.contextShift(ExecutionContexts.synchronous)
  val xa = Transactor.fromDriverManager[IO](
    "org.postgresql.Driver",
    "jdbc:postgresql://localhost:5432/mydatabase",
    "username",
    "password"
  )

  // Step 3: Define the SQL query
  val query = sql"SELECT id, timestamp_column FROM mytable".query[TimestampData]

  // Step 4: Execute the query and map the result
  val result: IO[List[TimestampData]] = query.to[List].transact(xa)

  // Step 5: Run the query and print the result
  result.unsafeRunSync().foreach(println)
}

import doobie._
import doobie.implicits._
import doobie.util.ExecutionContexts
import cats.effect.IO
import java.util.Date

object Main extends App {
  // Step 1: Create a case class to hold the data
  case class TimestampData(id: Int, timestamp: Date)

  // Step 2: Create a database connection pool
  implicit val cs = IO.contextShift(ExecutionContexts.synchronous)
  val xa = Transactor.fromDriverManager[IO](
    "org.postgresql.Driver",
    "jdbc:postgresql://localhost:5432/mydatabase",
    "username",
    "password"
  )

  // Step 3: Define the SQL update statement
  val update = sql"UPDATE mytable SET timestamp_column = ${new Date()} WHERE id = 1".update

  // Step 4: Execute the update statement
  val result: IO[Int] = update.run.transact(xa)

  // Step 5: Run the update statement and print the number of affected rows
  val affectedRows = result.unsafeRunSync()
  println(s"Affected rows: $affectedRows")
}