Erik Darling digs into a new series:
To start things off, we’re going to talk about query plan patterns related to windowing functions.
There are several things to consider with windowing function query plans:
– Row vs Batch mode
– With and Without Partition By
– Index Support for Partition and Order By
– Column SELECTion
– Rows vs Range/Global aggregatesWe’ll get to them in separate posts, because there are particulars about them that would make covering them all in a single post unwieldy.
Anyway, the first one is pretty simple, and starting simple is about my speed.
Read on for this quick coverage of row mode versus batch mode processing with respect to window functions.