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I have attached a patch to allow GROUP BY and/or ORDER BY function or expressions. Note worthy items: 1. The expression or function need not be in the target list. Example: SELECT name FROM foo GROUP BY lower(name); 2. Simplified the grammar to use expressions only. 3. Cleaned up earlier patch in this area to make use of existing utility functions. 3. Reduced some of the members in the SortGroupBy parse node. The original data members were redundant with the new expression node. (MUST do a "make clean" now) 4. Added a new parse node "JoinUsing". The JOIN USING clause was overloading this SortGroupBy structure. With the afore mentioned reduction of members, the two clauses lost all their commonality. 5. A bug still exist where, if a function or expression is GROUPed BY, and an aggregate function does not include a attribute from the expression or function, the backend crashes. (or something like that) The bug pre-dates this patch. Example: SELECT lower(a) AS lowcase, count(b) FROM foo GROUP BY lowcase; *** BOOM *** --Also when not in target list SELECT count(b) FROM foo GROUP BY lower(a); *** BOOM AGAIN *** |
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PostgreSQL Data Base Management System (formerly known as Postgres, then as Postgres95). This directory contains the version 6.3.2 release of the PostgreSQL database server. The server is not ANSI SQL compliant, but it gets closer with every release. After you unzip and untar the distribution file, look at file INSTALL for the installation notes and file HISTORY for the changes. The latest version of this software may be obtained at ftp://ftp.postgresql.org/pub/. For more information look at our WWW home page located at http://www.postgreSQL.org/. PostgreSQL is not public domain software. It is copyrighted by the University of California but may be used according to the licensing terms of the the copyright below: ------------------------------------------------------------------------ POSTGRES95 Data Base Management System (formerly known as Postgres, then as Postgres95). Copyright (c) 1994-7 Regents of the University of California Permission to use, copy, modify, and distribute this software and its documentation for any purpose, without fee, and without a written agreement is hereby granted, provided that the above copyright notice and this paragraph and the following two paragraphs appear in all copies. IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATIONS TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.