Tom Lane a9d9acbf21 Create infrastructure for moving-aggregate optimization. ... Until now, when executing an aggregate function as a window function within a window with moving frame start (that is, any frame start mode except UNBOUNDED PRECEDING), we had to recalculate the aggregate from scratch each time the frame head moved. This patch allows an aggregate definition to include an alternate "moving aggregate" implementation that includes an inverse transition function for removing rows from the aggregate's running state. As long as this can be done successfully, runtime is proportional to the total number of input rows, rather than to the number of input rows times the average frame length. This commit includes the core infrastructure, documentation, and regression tests using user-defined aggregates. Follow-on commits will update some of the built-in aggregates to use this feature. David Rowley and Florian Pflug, reviewed by Dean Rasheed; additional hacking by me		2014-04-12 12:03:30 -04:00
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src	Create infrastructure for moving-aggregate optimization.	2014-04-12 12:03:30 -04:00
bug.template	Stamp HEAD as 9.4devel.	2013-06-14 14:41:28 -04:00
KNOWN_BUGS	Remove extra newlines at end and beginning of files, add missing newlines	2010-08-19 05:57:36 +00:00
Makefile	Remove maintainer-check target, fold into normal build	2013-10-10 20:11:56 -04:00
MISSING_FEATURES	Remove extra newlines at end and beginning of files, add missing newlines	2010-08-19 05:57:36 +00:00
TODO	Update URL.	2008-08-21 20:15:31 +00:00