database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-08-30 06:01:21 +03:00
Code Activity

Add some basic support for window frame clauses to the window-functions

Browse Source 
patch.  This includes the ability to force the frame to cover the whole
partition, and the ability to make the frame end exactly on the current row
rather than its last ORDER BY peer.  Supporting any more of the full SQL
frame-clause syntax will require nontrivial hacking on the window aggregate
code, so it'll have to wait for 8.5 or beyond.
This commit is contained in:
Tom Lane
2008-12-31 00:08:39 +00:00
parent 0fb9be7acf
commit 8e8854daa2
24 changed files with 757 additions and 307 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
doc/src/sgml/queries.sgml
View File

@@ -1,4 +1,4 @@
<!-- $PostgreSQL: pgsql/doc/src/sgml/queries.sgml,v 1.51 2008/12/28 18:53:54 tgl Exp $ -->
<!-- $PostgreSQL: pgsql/doc/src/sgml/queries.sgml,v 1.52 2008/12/31 00:08:35 tgl Exp $ -->
<chapter id="queries">
<title>Queries</title>
@@ -993,7 +993,7 @@ SELECT product_id, p.name, (sum(s.units) * (p.price - p.cost)) AS profit
</para>
<para>
Currently, use of window functions always forces sorting, and so the
Currently, window functions always require presorted data, and so the
query output will be ordered according to one or another of the window
functions' <literal>PARTITION BY</>/<literal>ORDER BY</> clauses.
It is not recommendable to rely on this, however. Use an explicit