Github user davies commented on a diff in the pull request:
https://github.com/apache/spark/pull/6988#discussion_r35704132
--- Diff:
sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/datetimeFunctions.scala
---
@@ -337,3 +356,49 @@ case class NextDay(startDate: Expression, dayOfWeek:
Expression)
})
}
}
+
+/**
+ * Returns date truncated to the unit specified by the format.
+ */
+case class Trunc(date: Expression, format: Expression)
+ extends BinaryExpression with ImplicitCastInputTypes {
+ override def left: Expression = date
+ override def right: Expression = format
+
+ override def inputTypes: Seq[AbstractDataType] = Seq(DateType,
StringType)
+ override def dataType: DataType = DateType
+
+ override def nullSafeEval(d: Any, fmt: Any): Any = {
+ val minItem = DateTimeUtils.getFmt(fmt.asInstanceOf[UTF8String])
+ if (minItem == -1) {
+ // unknown format
+ null
+ } else {
+ val days = d.asInstanceOf[Int]
+ if (minItem == Calendar.YEAR) {
+ days - DateTimeUtils.getDayInYear(days) + 1
+ } else {
+ // trunc to MONTH
+ days - DateTimeUtils.getDayOfMonth(days) + 1
+ }
+ }
+ }
+
+ override def genCode(ctx: CodeGenContext, ev: GeneratedExpressionCode):
String = {
+ nullSafeCodeGen(ctx, ev, (dateVal, fmt) => {
+ val dtu = DateTimeUtils.getClass.getName.stripSuffix("$")
+ val form = ctx.freshName("form")
+ s"""
+ int $form = $dtu.getFmt($fmt);
+ if ($form == ${Calendar.YEAR}) {
--- End diff --
Could you put these into DateTimeUtils? And add tests for it.
---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at [email protected] or file a JIRA ticket
with INFRA.
---
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
