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* Update copyrights in source tree to 2008.Bruce Momjian2008-01-01
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* pgindent run for 8.3.Bruce Momjian2007-11-15
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* Fix parameter recalculation for Limit nodes: during a ReScan call we mustTom Lane2007-05-17
| | | | | | | | | | | | | recompute the limit/offset immediately, so that the updated values are available when the child's ReScan function is invoked. Add a regression test for this, too. Bug is new in HEAD (due to the bounded-sorting patch) so no need for back-patch. I did not do anything about merging this signaling with chgParam processing, but if we were to do that we'd still need to compute the updated values at this point rather than during the first ProcNode call. Per observation and test case from Greg Stark, though I didn't use his patch.
* Teach tuplesort.c about "top N" sorting, in which only the first N tuplesTom Lane2007-05-04
| | | | | | | | | | need be returned. We keep a heap of the current best N tuples and sift-up new tuples into it as we scan the input. For M input tuples this means only about M*log(N) comparisons instead of M*log(M), not to mention a lot less workspace when N is small --- avoiding spill-to-disk for large M is actually the most attractive thing about it. Patch includes planner and executor support for invoking this facility in ORDER BY ... LIMIT queries. Greg Stark, with some editorialization by moi.
* Update CVS HEAD for 2007 copyright. Back branches are typically notBruce Momjian2007-01-05
| | | | back-stamped for this.
* Fix LIMIT/OFFSET for null limit values. This worked before 8.2 but was brokenTom Lane2006-12-03
| | | | | | by the change to make limit values int8 instead of int4. (Specifically, you can do DatumGetInt32 safely on a null value, but not DatumGetInt64.) Per bug #2803 from Greg Johnson.
* Code review for bigint-LIMIT patch. Fix missed planner dependency,Tom Lane2006-07-26
| | | | | | eliminate unnecessary code, force initdb because stored rules change (limit nodes are now supposed to be int8 not int4 expressions). Update comments and error messages, which still all said 'integer'.
* Change LIMIT/OFFSET to use int8Bruce Momjian2006-07-26
| | | | Dhanaraj M
* Update copyright for 2006. Update scripts.Bruce Momjian2006-03-05
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* Extend the ExecInitNode API so that plan nodes receive a set of flagTom Lane2006-02-28
| | | | | | | | | | | | 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
* Get rid of ExecAssignResultTypeFromOuterPlan() and make all plan node typesTom Lane2005-11-23
| | | | | | | | | | | generate their output tuple descriptors from their target lists (ie, using ExecAssignResultTypeFromTL()). We long ago fixed things so that all node types have minimally valid tlists, so there's no longer any good reason to have two different ways of doing it. This change is needed to fix bug reported by Hayden James: the fix of 2005-11-03 to emit the correct column names after optimizing away a SubqueryScan node didn't work if the new top-level plan node used ExecAssignResultTypeFromOuterPlan to generate its tupdesc, since the next plan node down won't have the correct column labels.
* Standard pgindent run for 8.1.Bruce Momjian2005-10-15
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* Revise TupleTableSlot code to avoid unnecessary construction and disassemblyTom Lane2005-03-16
| | | | | | | | | | | | | | | | | | | | | 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.
* Tag appropriate files for rc3PostgreSQL Daemon2004-12-31
| | | | | | | | 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 ...
* Update copyright to 2004.Bruce Momjian2004-08-29
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* $Header: -> $PostgreSQL Changes ...PostgreSQL Daemon2003-11-29
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* Update copyrights to 2003.Bruce Momjian2003-08-04
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* pgindent run.Bruce Momjian2003-08-04
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* Error message editing in backend/executor.Tom Lane2003-07-21
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* Revise executor APIs so that all per-query state structure is built inTom Lane2002-12-15
| | | | | | 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.
* Phase 3 of read-only-plans project: ExecInitExpr now builds expressionTom Lane2002-12-13
| | | | | | | 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.
* Phase 1 of read-only-plans project: cause executor state nodes to pointTom Lane2002-12-05
| | | | | | | | | | 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.
* Redesign internal logic of nodeLimit so that it does not need to fetchTom Lane2002-11-22
| | | | | | one more row from the subplan than the COUNT would appear to require. This costs a little more logic but a number of people have complained about the old implementation.
* Update copyright to 2002.Bruce Momjian2002-06-20
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* Another pgindent run. Fixes enum indenting, and improves #endifBruce Momjian2001-10-28
| | | | spacing. Also adds space for one-line comments.
* pgindent run on all C files. Java run to follow. initdb/regressionBruce Momjian2001-10-25
| | | | tests pass.
* Evaluate LIMIT/OFFSET expressions with ExecEvalExprSwitchContext, notTom Lane2001-08-06
| | | | ExecEvalExpr, to avoid possible memory leak.
* Fix comments that were mis-wrapped, for Tom Lane.Bruce Momjian2001-03-23
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* Remove dashes in comments that don't need them, rewrap with pgindent.Bruce Momjian2001-03-22
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* pgindent run. Make it all clean.Bruce Momjian2001-03-22
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* Change Copyright from PostgreSQL, Inc to PostgreSQL Global Development Group.Bruce Momjian2001-01-24
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* Allow ORDER BY, LIMIT in sub-selects. Fix most (not all) cases whereTom Lane2000-11-05
| | | | | | the grammar did not allow redundant parentheses around sub-selects. Distinguish LIMIT ALL from LIMIT 0; make the latter behave as one would expect.
* Re-implement LIMIT/OFFSET as a plan node type, instead of a hack inTom Lane2000-10-26
ExecutorRun. This allows LIMIT to work in a view. Also, LIMIT in a cursor declaration will behave in a reasonable fashion, whereas before it was overridden by the FETCH count.