Commit Graph

25 Commits

Author SHA1 Message Date
Bruce Momjian f3c3deb7d0 Update copyrights to 2003. 2003-08-04 02:40:20 +00:00
Tom Lane 1afac12910 Create a new file executor/execGrouping.c to centralize utility routines
shared by nodeGroup, nodeAgg, and soon nodeSubplan.
2003-01-10 23:54:24 +00:00
Tom Lane 1fd0c59e25 Phase 1 of read-only-plans project: cause executor state nodes to point
to plan nodes, not vice-versa.  All executor state nodes now inherit from
struct PlanState.  Copying of plan trees has been simplified by not
storing a list of SubPlans in Plan nodes (eliminating duplicate links).
The executor still needs such a list, but it can build it during
ExecutorStart since it has to scan the plan tree anyway.
No initdb forced since no stored-on-disk structures changed, but you
will need a full recompile because of node-numbering changes.
2002-12-05 15:50:39 +00:00
Bruce Momjian d84fe82230 Update copyright to 2002. 2002-06-20 20:29:54 +00:00
Bruce Momjian ea08e6cd55 New pgindent run with fixes suggested by Tom. Patch manually reviewed,
initdb/regression tests pass.
2001-11-05 17:46:40 +00:00
Bruce Momjian 6783b2372e Another pgindent run. Fixes enum indenting, and improves #endif
spacing.  Also adds space for one-line comments.
2001-10-28 06:26:15 +00:00
Bruce Momjian b81844b173 pgindent run on all C files. Java run to follow. initdb/regression
tests pass.
2001-10-25 05:50:21 +00:00
Bruce Momjian 623bf843d2 Change Copyright from PostgreSQL, Inc to PostgreSQL Global Development Group. 2001-01-24 19:43:33 +00:00
Tom Lane badce86a2c First stage of reclaiming memory in executor by resetting short-term
memory contexts.  Currently, only leaks in expressions executed as
quals or projections are handled.  Clean up some old dead cruft in
executor while at it --- unused fields in state nodes, that sort of thing.
2000-07-12 02:37:39 +00:00
Bruce Momjian 52f77df613 Ye-old pgindent run. Same 4-space tabs. 2000-04-12 17:17:23 +00:00
Tom Lane dd979f66be Redesign DISTINCT ON as discussed in pgsql-sql 1/25/00: syntax is now
SELECT DISTINCT ON (expr [, expr ...]) targetlist ...
and there is a check to make sure that the user didn't specify an ORDER BY
that's incompatible with the DISTINCT operation.
Reimplement nodeUnique and nodeGroup to use the proper datatype-specific
equality function for each column being compared --- they used to do
bitwise comparisons or convert the data to text strings and strcmp().
(To add insult to injury, they'd look up the conversion functions once
for each tuple...)  Parse/plan representation of DISTINCT is now a list
of SortClause nodes.
initdb forced by querytree change...
2000-01-27 18:11:50 +00:00
Tom Lane 91250f3854 Remove duplicate extern declaration. 2000-01-26 23:48:05 +00:00
Bruce Momjian 5c25d60244 Add:
* Portions Copyright (c) 1996-2000, PostgreSQL, Inc

to all files copyright Regents of Berkeley.  Man, that's a lot of files.
2000-01-26 05:58:53 +00:00
Bruce Momjian 4b2c2850bf Clean up #include in /include directory. Add scripts for checking includes. 1999-07-15 15:21:54 +00:00
Bruce Momjian ad4948862c Remove S*I comments from Stephan. 1999-07-13 21:17:45 +00:00
Bruce Momjian 07842084fe pgindent run over code. 1999-05-25 16:15:34 +00:00
Bruce Momjian 6724a50787 Change my-function-name-- to my_function_name, and optimizer renames. 1999-02-13 23:22:53 +00:00
Bruce Momjian bd8ffc6f3f Hi!
INTERSECT and EXCEPT is available for postgresql-v6.4!

The patch against v6.4 is included at the end of the current text
(in uuencoded form!)

I also included the text of my Master's Thesis. (a postscript
version). I hope that you find something of it useful and would be
happy if parts of it find their way into the PostgreSQL documentation
project (If so, tell me, then I send the sources of the document!)

The contents of the document are:
  -) The first chapter might be of less interest as it gives only an
     overview on SQL.

  -) The second chapter gives a description on much of PostgreSQL's
     features (like user defined types etc. and how to use these features)

  -) The third chapter starts with an overview of PostgreSQL's internal
     structure with focus on the stages a query has to pass (i.e. parser,
     planner/optimizer, executor). Then a detailed description of the
     implementation of the Having clause and the Intersect/Except logic is
     given.

Originally I worked on v6.3.2 but never found time enough to prepare
and post a patch. Now I applied the changes to v6.4 to get Intersect
and Except working with the new version. Chapter 3 of my documentation
deals with the changes against v6.3.2, so keep that in mind when
comparing the parts of the code printed there with the patched sources
of v6.4.

Here are some remarks on the patch. There are some things that have
still to be done but at the moment I don't have time to do them
myself. (I'm doing my military service at the moment) Sorry for that
:-(

-) I used a rewrite technique for the implementation of the Except/Intersect
   logic which rewrites the query to a semantically equivalent query before
   it is handed to the rewrite system (for views, rules etc.), planner,
   executor etc.

-) In v6.3.2 the types of the attributes of two select statements
   connected by the UNION keyword had to match 100%. In v6.4 the types
   only need to be familiar (i.e. int and float can be mixed). Since this
   feature did not exist when I worked on Intersect/Except it
   does not work correctly for Except/Intersect queries WHEN USED IN
   COMBINATION WITH UNIONS! (i.e. sometimes the wrong type is used for the
   resulting table. This is because until now the types of the attributes of
   the first select statement have been used for the resulting table.
   When Intersects and/or Excepts are used in combination with Unions it
   might happen, that the first select statement of the original query
   appears at another position in the query which will be executed. The reason
   for this is the technique used for the implementation of
   Except/Intersect which does a query rewrite!)
   NOTE: It is NOT broken for pure UNION queries and pure INTERSECT/EXCEPT
         queries!!!

-) I had to add the field intersect_clause to some data structures
   but did not find time to implement printfuncs for the new field.
   This does NOT break the debug modes but when an Except/Intersect
   is used the query debug output will be the already rewritten query.

-) Massive changes to the grammar rules for SELECT and INSERT statements
   have been necessary (see comments in gram.y and documentation for
   deatails) in order to be able to use mixed queries like
   (SELECT ... UNION (SELECT ... EXCEPT SELECT)) INTERSECT SELECT...;

-) When using UNION/EXCEPT/INTERSECT you will get:
   NOTICE: equal: "Don't know if nodes of type xxx are equal".
   I did not have  time to add comparsion support for all the needed nodes,
   but the default behaviour of the function equal met my requirements.
   I did not dare to supress this message!

   That's the reason why the regression test for union will fail: These
   messages are also included in the union.out file!

-) Somebody of you changed the union_planner() function for v6.4
   (I copied the targetlist to new_tlist and that was removed and
   replaced by a cleanup of the original targetlist). These chnages
   violated some having queries executed against views so I changed
   it back again. I did not have time to examine the differences between the
   two versions but now it works :-)
   If you want to find out, try the file queries/view_having.sql on
   both versions and compare the results . Two queries won't produce a
   correct result with your version.

regards

    Stefan
1999-01-18 00:10:17 +00:00
Bruce Momjian fa1a8d6a97 OK, folks, here is the pgindent output. 1998-09-01 04:40:42 +00:00
Bruce Momjian 4f807be2ad Patch for ReScan of Group. 1998-07-16 01:49:19 +00:00
Bruce Momjian 598e86f3b3 Cleanup up include files. 1997-11-26 01:14:33 +00:00
Bruce Momjian 59f6a57e59 Used modified version of indent that understands over 100 typedefs. 1997-09-08 21:56:23 +00:00
Bruce Momjian 319dbfa736 Another PGINDENT run that changes variable indenting and case label indenting. Also static variable indenting. 1997-09-08 02:41:22 +00:00
Bruce Momjian 1ccd423235 Massive commit to run PGINDENT on all *.c and *.h files. 1997-09-07 05:04:48 +00:00
Marc G. Fournier 870be9fa8e Clean up th ecompile process by centralizing the include files
- code compile tested, but due to a yet unresolved problem with
          parse.h's creation, compile not completed...
1996-08-28 07:27:54 +00:00