Github user anabranch commented on a diff in the pull request:

    https://github.com/apache/spark/pull/16138#discussion_r91134077
  
    --- Diff: 
sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/datetimeExpressions.scala
 ---
    @@ -1047,6 +1047,53 @@ case class ToDate(child: Expression) extends 
UnaryExpression with ImplicitCastIn
     }
     
     /**
    + * Parses a column with a format to a timestamp.
    + */
    +@ExpressionDescription(
    +  usage = "_FUNC_(timestamp_str, fmt) - Parses the `timestamp` expression 
" +
    +    "with the `fmt` expression.",
    +  extended = """
    +    Examples:
    +      > SELECT _FUNC_('2016-12-31', 'yyyy-MM-dd');
    +       2016-12-31
    +             """)
    +case class ParseToDate(left: Expression, right: Expression, child: 
Expression)
    +  extends RuntimeReplaceable with ImplicitCastInputTypes {
    +
    +  def this(left: Expression, format: Expression) = {
    +    this(left, format, ToDate(new ParseToTimestamp(left, format)))
    +  }
    +
    +  override def inputTypes: Seq[AbstractDataType] = Seq(StringType, 
StringType)
    +  override def dataType: DataType = DateType
    +  override def flatArguments: Iterator[Any] = Iterator(left, right)
    +  override def sql: String = s"$prettyName(${left.sql}, ${right.sql})"
    +}
    +
    +/**
    + * Parses a column with a format to a timestamp.
    + */
    +@ExpressionDescription(
    +  usage = "_FUNC_(timestamp, fmt) - Parses the `timestamp` expression with 
the `fmt` expression.",
    +  extended = """
    +    Examples:
    +      > SELECT _FUNC_('2016-12-31', 'yyyy-MM-dd');
    +       2016-12-31 00:00:00.0
    +  """)
    +case class ParseToTimestamp(left: Expression, right: Expression, child: 
Expression)
    +  extends RuntimeReplaceable with ImplicitCastInputTypes {
    +
    +  def this(left: Expression, format: Expression) = {
    +  this(left, format, Cast(UnixTimestamp(left, format), TimestampType))
    --- End diff --
    
    For reasons unbeknownst to me, Cast(...., TimestampType) is not equivalent 
to ....cast("timestamp")


---
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 infrastruct...@apache.org or file a JIRA ticket
with INFRA.
---

---------------------------------------------------------------------
To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org
For additional commands, e-mail: reviews-h...@spark.apache.org

Reply via email to