These are special functions that cannot be classified in other categories.
|BLANK||Returns a blank.|
|EARLIER||Returns the value in the column prior to the specified number of table scans (default is 1).|
|EARLIEST||Returns the value in the column for the very first point at which there was a row context.|
|ERROR||Raises a user specified error.|
|KEYWORDMATCH||Returns TRUE if there is a match between the MatchExpression and Text.|
Contributors: Alberto Ferrari, Marco Russo, John Keegan