TDV-Supported Analytical Functions
Analytical functions produce summaries, reports, and statistics on large amounts of static data. TDV supports more than three dozen such functions.
Analytical functions are OLAP (on-line analytic processing) functions that operate on large amounts of static data. Most SQL functions are OLTP (on-line transaction processing) functions that operate as quickly as possible on discrete amounts of dynamic, transactional data.
Analytical functions are generally characterized by an OVER keyword and a window clause. (See
Window Clause.)
Limitation
• Large data sets can be very slow when using analytical functions.
• Teradata does not support the RANGE keyword. It only supports the ROWS keyword.
• For analytical functions that support the windowing clause, TDV does not push to Teradata without you explicitly suppling the windowing clause. Teradata implicitly adds ROWS BETWEEN UNBOUNDED PRECEEDING AND UNBOUNDED FOLLOWING for analytical functions that do not supply a windowing clause. In TDV and ANSI SQL, RANGE UNBOUNDED PRECEDING is supplied.
• Teradata (version 16) does not support the RANGE keyword.
TDV supports the following analytical functions: