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2006-02-28Extend the ExecInitNode API so that plan nodes receive a set of flagTom Lane
bits indicating which optional capabilities can actually be exercised at runtime. This will allow Sort and Material nodes, and perhaps later other nodes, to avoid unnecessary overhead in common cases. This commit just adds the infrastructure and arranges to pass the correct flag values down to plan nodes; none of the actual optimizations are here yet. I'm committing this separately in case anyone wants to measure the added overhead. (It should be negligible.) Simon Riggs and Tom Lane
2005-10-15Standard pgindent run for 8.1.Bruce Momjian
2005-03-16Revise TupleTableSlot code to avoid unnecessary construction and disassemblyTom Lane
of tuples when passing data up through multiple plan nodes. A slot can now hold either a normal "physical" HeapTuple, or a "virtual" tuple consisting of Datum/isnull arrays. Upper plan levels can usually just copy the Datum arrays, avoiding heap_formtuple() and possible subsequent nocachegetattr() calls to extract the data again. This work extends Atsushi Ogawa's earlier patch, which provided the key idea of adding Datum arrays to TupleTableSlots. (I believe however that something like this was foreseen way back in Berkeley days --- see the old comment on ExecProject.) A test case involving many levels of join of fairly wide tables (about 80 columns altogether) showed about 3x overall speedup, though simple queries will probably not be helped very much. I have also duplicated some code in heaptuple.c in order to provide versions of heap_formtuple and friends that use "bool" arrays to indicate null attributes, instead of the old convention of "char" arrays containing either 'n' or ' '. This provides a better match to the convention used by ExecEvalExpr. While I have not made a concerted effort to get rid of uses of the old routines, I think they should be deprecated and eventually removed.
2005-03-10Make the behavior of HAVING without GROUP BY conform to the SQL spec.Tom Lane
Formerly, if such a clause contained no aggregate functions we mistakenly treated it as equivalent to WHERE. Per spec it must cause the query to be treated as a grouped query of a single group, the same as appearance of aggregate functions would do. Also, the HAVING filter must execute after aggregate function computation even if it itself contains no aggregate functions.
2004-12-31Tag appropriate files for rc3PostgreSQL Daemon
Also performed an initial run through of upgrading our Copyright date to extend to 2005 ... first run here was very simple ... change everything where: grep 1996-2004 && the word 'Copyright' ... scanned through the generated list with 'less' first, and after, to make sure that I only picked up the right entries ...
2004-08-29Update copyright to 2004.Bruce Momjian
2003-11-29$Header: -> $PostgreSQL Changes ...PostgreSQL Daemon
2003-08-04Update copyrights to 2003.Bruce Momjian
2003-01-12Fix wrong/misleading comments, be more consistent about where to callTom Lane
ExecAssignResultTypeFromTL().
2003-01-10Create a new file executor/execGrouping.c to centralize utility routinesTom Lane
shared by nodeGroup, nodeAgg, and soon nodeSubplan.
2002-12-15Revise executor APIs so that all per-query state structure is built inTom Lane
a per-query memory context created by CreateExecutorState --- and destroyed by FreeExecutorState. This provides a final solution to the longstanding problem of memory leaked by various ExecEndNode calls.
2002-12-13Phase 3 of read-only-plans project: ExecInitExpr now builds expressionTom Lane
execution state trees, and ExecEvalExpr takes an expression state tree not an expression plan tree. The plan tree is now read-only as far as the executor is concerned. Next step is to begin actually exploiting this property.
2002-12-05Phase 1 of read-only-plans project: cause executor state nodes to pointTom Lane
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.
2002-11-29Tighten selection of equality and ordering operators for groupingTom Lane
operations: make sure we use operators that are compatible, as determined by a mergejoin link in pg_operator. Also, add code to planner to ensure we don't try to use hashed grouping when the grouping operators aren't marked hashable.
2002-11-06Phase 2 of hashed-aggregation project. nodeAgg.c now knows how to doTom Lane
hashed aggregation, but there's not yet planner support for it.
2002-11-06First phase of implementing hash-based grouping/aggregation. An AGG planTom Lane
node now does its own grouping of the input rows, and has no need for a preceding GROUP node in the plan pipeline. This allows elimination of the misnamed tuplePerGroup option for GROUP, and actually saves more code in nodeGroup.c than it costs in nodeAgg.c, as well as being presumably faster. Restructure the API of query_planner so that we do not commit to using a sorted or unsorted plan in query_planner; instead grouping_planner makes the decision. (Right now it isn't any smarter than query_planner was, but that will change as soon as it has the option to select a hash- based aggregation step.) Despite all the hackery, no initdb needed since only in-memory node types changed.
2002-06-20Update copyright to 2002.Bruce Momjian
2002-05-17Get rid of the last few uses of typeidTypeName() rather thanTom Lane
format_type_be() in error messages.
2002-04-16Operators live in namespaces. CREATE/DROP/COMMENT ON OPERATOR takeTom Lane
qualified operator names directly, for example CREATE OPERATOR myschema.+ ( ... ). To qualify an operator name in an expression you need to write OPERATOR(myschema.+) (thanks to Peter for suggesting an escape hatch). I also took advantage of having to reformat pg_operator to fix something that'd been bugging me for a while: mergejoinable operators should have explicit links to the associated cross-data-type comparison operators, rather than hardwiring an assumption that they are named < and >.
2001-10-25pgindent run on all C files. Java run to follow. initdb/regressionBruce Momjian
tests pass.
2001-03-22Remove dashes in comments that don't need them, rewrap with pgindent.Bruce Momjian
2001-03-22pgindent run. Make it all clean.Bruce Momjian
2001-02-16Clean up two rather nasty bugs in operator selection code.Tom Lane
1. If there is exactly one pg_operator entry of the right name and oprkind, oper() and related routines would return that entry whether its input type had anything to do with the request or not. This is just premature optimization: we shouldn't return the single candidate until after we verify that it really is a valid candidate, ie, is at least coercion-compatible with the given types. 2. oper() and related routines only promise a coercion-compatible result. Unfortunately, there were quite a few callers that assumed the returned operator is binary-compatible with the given datatype; they would proceed to call it without making any datatype coercions. These callers include sorting, grouping, aggregation, and VACUUM ANALYZE. In general I think it is appropriate for these callers to require an exact or binary-compatible match, so I've added a new routine compatible_oper() that only succeeds if it can find an operator that doesn't require any run-time conversions. Callers now call oper() or compatible_oper() depending on whether they are prepared to deal with type conversion or not. The upshot of these bugs is revealed by the following silliness in PL/Tcl's selftest: it creates an operator @< on int4, and then tries to use it to sort a char(N) column. The system would let it do that :-( (and evidently has done so since 6.3 :-( :-(). The result in this case was just a silly sort order, but the reverse combination would've provoked coredump from trying to dereference integers. With this fix you get more reasonable behavior: pltcl_test=# select * from T_pkey1 order by key1, key2 using @<; ERROR: Unable to identify an operator '@<' for types 'bpchar' and 'bpchar' You will have to retype this query using an explicit cast
2001-01-24Change Copyright from PostgreSQL, Inc to PostgreSQL Global Development Group.Bruce Momjian
2000-11-16Change SearchSysCache coding conventions so that a reference count isTom Lane
maintained for each cache entry. A cache entry will not be freed until the matching ReleaseSysCache call has been executed. This eliminates worries about cache entries getting dropped while still in use. See my posting to pg-hackers of even date for more info.
2000-08-24SQL-language functions are now callable in ordinary fmgr contexts ...Tom Lane
for example, an SQL function can be used in a functional index. (I make no promises about speed, but it'll work ;-).) Clean up and simplify handling of functions returning sets.
2000-07-12First stage of reclaiming memory in executor by resetting short-termTom Lane
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.
2000-05-30Third round of fmgr updates: eliminate calls using fmgr() andTom Lane
fmgr_faddr() in favor of new-style calls. Lots of cleanup of sloppy casts to use XXXGetDatum and DatumGetXXX ...
2000-05-30Remove unused include files. Do not touch /port or includes used by defines.Bruce Momjian
2000-04-12Ye-old pgindent run. Same 4-space tabs.Bruce Momjian
2000-01-27Redesign DISTINCT ON as discussed in pgsql-sql 1/25/00: syntax is nowTom Lane
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...
2000-01-26Add:Bruce Momjian
* Portions Copyright (c) 1996-2000, PostgreSQL, Inc to all files copyright Regents of Berkeley. Man, that's a lot of files.
1999-12-16Some changes to prepare for LONG attributes.Jan Wieck
Jan
1999-09-24Several changes here, not very related but touching some of the same files.Tom Lane
* Buffer refcount cleanup (per my "progress report" to pghackers, 9/22). * Add links to backend PROC structs to sinval's array of per-backend info, and use these links for routines that need to check the state of all backends (rather than the slow, complicated search of the ShmemIndex hashtable that was used before). Add databaseOID to PROC structs. * Use this to implement an interlock that prevents DESTROY DATABASE of a database containing running backends. (It's a little tricky to prevent a concurrently-starting backend from getting in there, since the new backend is not able to lock anything at the time it tries to look up its database in pg_database. My solution is to recheck that the DB is OK at the end of InitPostgres. It may not be a 100% solution, but it's a lot better than no interlock at all...) * In ALTER TABLE RENAME, flush buffers for the relation before doing the rename of the physical files, to ensure we don't get failures later from mdblindwrt(). * Update TRUNCATE patch so that it actually compiles against current sources :-(. You should do "make clean all" after pulling these changes.
1999-07-17 Move some system includes into c.h, and remove duplicates.Bruce Momjian
1999-07-15Remove unused #includes in *.c files.Bruce Momjian
1999-07-11ExecReScanGroup() forgot to clear grpstate->grp_firstTuple,Tom Lane
thereby guaranteeing wrong results from a rescanned Group node.
1999-05-25pgindent run over code.Bruce Momjian
1999-02-13Change my-function-name-- to my_function_name, and optimizer renames.Bruce Momjian
1999-01-24Replace typtoout() and gettypelem() with a single routine,Tom Lane
so that fetching an attribute value needs only one SearchSysCacheTuple call instead of two redundant searches. This speeds up a large SELECT by about ten percent, and probably will help GROUP BY and SELECT DISTINCT too.
1998-11-27New HeapTuple structure/interface.Vadim B. Mikheev
1998-09-01OK, folks, here is the pgindent output.Bruce Momjian
1998-07-16Fix for Group ReScan suggested by Vadim.Bruce Momjian
1998-07-16Patch for ReScan of Group.Bruce Momjian
1998-06-15Remove un-needed braces around single statements.Bruce Momjian
1998-02-26pgindent run before 6.3 release, with Thomas' requested changes.Bruce Momjian
1998-02-18New nodeGroup.c code uses own copy of first tuple in a group.Vadim B. Mikheev
Free memory after comparison in nodeUnique.c
1998-02-10Pass around typmod as int16.Bruce Momjian
1998-02-10Pass attypmod through to executor by adding to Var and Resdom.Bruce Momjian
1998-01-31Inline fastgetattr and others so data access does not use functionBruce Momjian
calls.