Slick: Filtering all records that have a joda date date equal to today's

Question

One way to achieve this would be as follows:

val now = DateTime.now

val today = now.toLocalDate
val tomorrow = today.plusDays(1)

val startOfToday = today.toDateTimeAtStartOfDay(now.getZone)
val startOfTomorrow = tomorrow.toDateTimeAtStartOfDay(now.getZone)

val todayLogItems = logItems.filter(logItem =>
  logItem.MyDateTime >= startOfToday && logItem.MyDateTime < startOfTomorrow
).list

Is there a way to write a query in a more concise way? Something in the lines:

logItems.filter(_.MyDateTime.toDate == DateTime.now.toDate).list

I ask this because in LINQ to NHibernate this is achievable ( Retrieving records by date only by comparing days using nhibernate ).

Answer 1

Slick joda, , . , , : * http://slick.typesafe.com/doc/2.0.0/userdefined.html * http://slick.typesafe.com/doc/2.0.0/api/#scala.slick.lifted.ExtensionMethods * https://github.com/slick/slick/blob/2.0.0/src/main/scala/scala/slick/lifted/ExtensionMethods.scala

- , Slick: https://github.com/slick/slick/issues/627

Answer 2

, LocalDateTimes, LocalDates:

val today = LocalDate.now
val todayLogItems = logItems.filter(_.MyDateTime.toLocalDate isEqual today)

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:

def equalsDate(dt: LocalDate) = {
  val start = dt.toDateTimeAtStartOfDay()
  val end = dt.plusDays(1).toDateTimeAtStartOfDay()
  (col: Column[DateTime]) => {
    col >= start && col < end
  }
}

val isToday = equalsDate(LocalDate.now)
val todayLogItems = logItems.filter(x => isToday(x.MyDateTime))