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2009-10-30Make the overflow guards in ExecChooseHashTableSize be more protective.Tom Lane
The original coding ensured nbuckets and nbatch didn't exceed INT_MAX, which while not insane on its own terms did nothing to protect subsequent code like "palloc(nbatch * sizeof(BufFile *))". Since enormous join size estimates might well be planner error rather than reality, it seems best to constrain the initial sizes to be not more than work_mem/sizeof(pointer), thus ensuring the allocated arrays don't exceed work_mem. We will allow nbatch to get bigger than that during subsequent ExecHashIncreaseNumBatches calls, but we should still guard against integer overflow in those palloc requests. Per bug #5145 from Bernt Marius Johnsen. Although the given test case only seems to fail back to 8.2, previous releases have variants of this issue, so patch all supported branches.
2009-10-02Ensure that a cursor has an immutable snapshot throughout its lifespan.Alvaro Herrera
The old coding was using a regular snapshot, referenced elsewhere, that was subject to having its command counter updated. Fix by creating a private copy of the snapshot exclusively for the cursor. Backpatch to 8.4, which is when the bug was introduced during the snapshot management rewrite.
2009-08-23Tweak ExecIndexEvalRuntimeKeys to forcibly detoast any toasted comparisonTom Lane
values before they get passed to the index access method. This avoids repeated detoastings that will otherwise ensue as the comparison value is examined by various index support functions. We have seen a couple of reports of cases where repeated detoastings result in an order-of-magnitude slowdown, so it seems worth adding a bit of extra logic to prevent this. I had previously proposed trying to avoid duplicate detoastings in general, but this fix takes care of what seems the most important case in practice with very little effort or risk. Back-patch to 8.4 so that the PostGIS folk won't have to wait a year to have this fix in a production release. (The issue exists further back, of course, but the code's diverged enough to make backpatching further a higher-risk action. Also it appears that the possible gains may be limited in prior releases because of different handling of lossy operators.)
2009-07-23In a non-hashed Agg node, reset the "aggcontext" at group boundaries, insteadTom Lane
of individually pfree'ing pass-by-reference transition values. This should be at least as fast as the prior coding, and it has the major advantage of clearing out any working data an aggregate function may have stored in or underneath the aggcontext. This avoids memory leakage when an aggregate such as array_agg() is used in GROUP BY mode. Per report from Chris Spotts. Back-patch to 8.4. In principle the problem could arise in prior versions, but since they didn't have array_agg the issue seems not critical.
2009-07-18Fix error cleanup failure caused by 8.4 changes in plpgsql to try to avoidTom Lane
memory leakage in error recovery. We were calling FreeExprContext, and therefore invoking ExprContextCallback callbacks, in both normal and error exits from subtransactions. However this isn't very safe, as shown in recent trouble report from Frank van Vugt, in which releasing a tupledesc refcount failed. It's also unnecessary, since the resources that callbacks might wish to release should be cleaned up by other error recovery mechanisms (ie the resource owners). We only really want FreeExprContext to release memory attached to the exprcontext in the error-exit case. So, add a bool parameter to FreeExprContext to tell it not to call the callbacks. A more general solution would be to pass the isCommit bool parameter on to the callbacks, so they could do only safe things during error exit. But that would make the patch significantly more invasive and possibly break third-party code that registers ExprContextCallback callbacks. We might want to do that later in HEAD, but for now I'll just do what seems reasonable to back-patch.
2009-06-20Fix things so that array_agg_finalfn does not modify or free its inputTom Lane
ArrayBuildState, per trouble report from Merlin Moncure. By adopting this fix, we are essentially deciding that aggregate final-functions should not modify their inputs ever. Adjust documentation and comments to match that conclusion.
2009-06-17ExecAgg() failed to finish running out set-returning functions in the lastTom Lane
aggregated tuple of a run. Per report from Laurenz Albe. This is a new bug in 8.4, but only because prior versions rejected SRFs in an Agg plan node altogether.
2009-06-11Revisit AlterTableCreateToastTable's API once again, hoping to make it whatTom Lane
pg_migrator actually needs and not just a partial solution. We have to be able to specify the OID that the new toast table should be created with.
2009-06-11Fix things so that you can still do "select foo()" where foo is a SQLTom Lane
function returning setof record. This used to work, more or less accidentally, but I had broken it while extending the code to allow materialize-mode functions to be called in select lists. Add a regression test case so it doesn't get broken again. Per gripe from Greg Davidson.
2009-06-118.4 pgindent run, with new combined Linux/FreeBSD/MinGW typedef listBruce Momjian
provided by Andrew.
2009-06-09Fix xmlattribute escaping XML special characters twice (bug #4822).Peter Eisentraut
Author: Itagaki Takahiro <itagaki.takahiro@oss.ntt.co.jp>
2009-06-04Improve the recently-added support for properly pluralized error messagesTom Lane
by extending the ereport() API to cater for pluralization directly. This is better than the original method of calling ngettext outside the elog.c code because (1) it avoids double translation, which wastes cycles and in the worst case could give a wrong result; and (2) it avoids having to use a different coding method in PL code than in the core backend. The client-side uses of ngettext are not touched since neither of these concerns is very pressing in the client environment. Per my proposal of yesterday.
2009-05-07Add an option to AlterTableCreateToastTable() to allow its caller to forceTom Lane
a toast table to be built, even if the sum-of-column-widths calculation indicates one isn't needed. This is needed by pg_migrator because if the old table has a toast table, we have to migrate over the toast table since it might contain some live data, even though subsequent column drops could mean that no recently-added rows could require toasting.
2009-04-08XMLATTRIBUTES() should send the attribute values throughPeter Eisentraut
map_sql_value_to_xml_value() instead of directly through the data type output function. This is per SQL standard, and consistent with XMLELEMENT().
2009-04-05Make ExecInitExpr build the list of SubPlans found in a plan tree in orderTom Lane
of discovery, rather than reverse order. This doesn't matter functionally (I suppose the previous coding dates from the time when lcons was markedly cheaper than lappend). However now that EXPLAIN is labeling subplans with IDs that are based on order of creation, this may help produce a slightly less surprising printout.
2009-04-02Refactor ExecProject and associated routines so that fast-path code is usedTom Lane
for simple Var targetlist entries all the time, even when there are other entries that are not simple Vars. Also, ensure that we prefetch attributes (with slot_getsomeattrs) for all Vars in the targetlist, even those buried within expressions. In combination these changes seem to significantly reduce the runtime for cases where tlists are mostly but not exclusively Vars. Per my proposal of yesterday.
2009-04-02Revert DTrace patch from Robert LorBruce Momjian
2009-04-02Add support for additional DTrace probes.Bruce Momjian
Robert Lor
2009-03-30Fix an oversight in the support for storing/retrieving "minimal tuples" inTom Lane
TupleTableSlots. We have functions for retrieving a minimal tuple from a slot after storing a regular tuple in it, or vice versa; but these were implemented by converting the internal storage from one format to the other. The problem with that is it invalidates any pass-by-reference Datums that were already fetched from the slot, since they'll be pointing into the just-freed version of the tuple. The known problem cases involve fetching both a whole-row variable and a pass-by-reference value from a slot that is fed from a tuplestore or tuplesort object. The added regression tests illustrate some simple cases, but there may be other failure scenarios traceable to the same bug. Note that the added tests probably only fail on unpatched code if it's built with --enable-cassert; otherwise the bug leads to fetching from freed memory, which will not have been overwritten without additional conditions. Fix by allowing a slot to contain both formats simultaneously; which turns out not to complicate the logic much at all, if anything it seems less contorted than before. Back-patch to 8.2, where minimal tuples were introduced.
2009-03-27Fix possible failures when a tuplestore switches from in-memory to on-diskTom Lane
mode while callers hold pointers to in-memory tuples. I reported this for the case of nodeWindowAgg's primary scan tuple, but inspection of the code shows that all of the calls in nodeWindowAgg and nodeCtescan are at risk. For the moment, fix it with a rather brute-force approach of copying whenever one of the at-risk callers requests a tuple. Later we might think of some sort of reference-count approach to reduce tuple copying.
2009-03-26Gettext plural supportPeter Eisentraut
In the backend, I changed only a handful of exemplary or important-looking instances to make use of the plural support; there is probably more work there. For the rest of the source, this should cover all relevant cases.
2009-03-21Optimize multi-batch hash joins when the outer relation has a nonuniformTom Lane
distribution, by creating a special fast path for the (first few) most common values of the outer relation. Tuples having hashvalues matching the MCVs are effectively forced to be in the first batch, so that we never write them out to the batch temp files. Bryce Cutt and Ramon Lawrence, with some editorialization by me.
2009-03-04Add new SQL:2008 error codes for invalid LIMIT and OFFSET values. RemovePeter Eisentraut
unused nonstandard error code that was perhaps intended for this but never used.
2009-02-08Ensure that INSERT ... SELECT into a table with OIDs never copies row OIDsTom Lane
from the source table. This could never happen anyway before 8.4 because the executor invariably applied a "junk filter" to rows due to be inserted; but now that we skip doing that when it's not necessary, the case can occur. Problem noted 2008-11-27 by KaiGai Kohei, though I misunderstood what he was on about at the time (the opacity of the patch he proposed didn't help).
2009-02-02Allow reloption names to have qualifiers, initially supporting a TOASTAlvaro Herrera
qualifier, and add support for this in pg_dump. This allows TOAST tables to have user-defined fillfactor, and will also enable us to move the autovacuum parameters to reloptions without taking away the possibility of setting values for TOAST tables.
2009-01-22Support column-level privileges, as required by SQL standard.Tom Lane
Stephen Frost, with help from KaiGai Kohei and others
2009-01-21Add new SPI_OK_REWRITTEN return code to SPI_execute and friends, for theHeikki Linnakangas
case that the command is rewritten into another type of command. The old behavior to return the command tag of the last executed command was pretty surprising. In PL/pgSQL, for example, it meant that if a command was rewritten to a utility statement, FOUND wasn't set at all.
2009-01-12Tweak order of operations in BitmapHeapNext() to avoid the case of prefetchingTom Lane
the same page we are nanoseconds away from reading for real. There should be something left to do on the current page before we consider issuing a prefetch.
2009-01-12Implement prefetching via posix_fadvise() for bitmap index scans. A newTom Lane
GUC variable effective_io_concurrency controls how many concurrent block prefetch requests will be issued. (The best way to handle this for plain index scans is still under debate, so that part is not applied yet --- tgl) Greg Stark
2009-01-10Revise the TIDBitmap API to support multiple concurrent iterations over aTom Lane
bitmap. This is extracted from Greg Stark's posix_fadvise patch; it seems worth committing separately, since it's potentially useful independently of posix_fadvise.
2009-01-09Arrange for function default arguments to be processed properly in expressionsTom Lane
that are set up for execution with ExecPrepareExpr rather than going through the full planner process. By introducing an explicit notion of "expression planning", this patch also lays a bit of groundwork for maybe someday allowing sub-selects in standalone expressions.
2009-01-07Insert conditional SPI_push/SPI_pop calls into InputFunctionCall,Tom Lane
OutputFunctionCall, and friends. This allows SPI-using functions to invoke datatype I/O without concern for the possibility that a SPI-using function will be called (which could be either the I/O function itself, or a function used in a domain check constraint). It's a tad ugly, but not nearly as ugly as what'd be needed to make this work via retail insertion of push/pop operations in all the PLs. This reverts my patch of 2007-01-30 that inserted some retail SPI_push/pop calls into plpgsql; that approach only fixed plpgsql, and not any other PLs. But the other PLs have the issue too, as illustrated by a recent gripe from Christian Schröder. Back-patch to 8.2, which is as far back as this solution will work. It's also as far back as we need to worry about the domain-constraint case, since earlier versions did not attempt to check domain constraints within datatype input. I'm not aware of any old I/O functions that use SPI themselves, so this should be sufficient for a back-patch.
2009-01-07Fix executor/spi.h to follow our usual conventions for include files, ie,Tom Lane
not include postgres.h nor anything else it doesn't directly need. Add #includes to calling files as needed to compensate. Per my proposal of yesterday. This should be noted as a source code change in the 8.4 release notes, since it's likely to require changes in add-on modules.
2009-01-02Include a pointer to the query's source text in QueryDesc structs. This isTom Lane
practically free given prior 8.4 changes in plancache and portal management, and it makes it a lot easier for ExecutorStart/Run/End hooks to get at the query text. Extracted from Itagaki Takahiro's pg_stat_statements patch, with minor editorialization.
2009-01-01Update copyright for 2009.Bruce Momjian
2008-12-31Add some basic support for window frame clauses to the window-functionsTom Lane
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.
2008-12-28Support window functions a la SQL:2008.Tom Lane
Hitoshi Harada, with some kibitzing from Heikki and Tom.
2008-12-27Make a couple of small changes to the tuplestore API, for the benefit of theTom Lane
upcoming window-functions patch. First, tuplestore_trim is now an exported function that must be explicitly invoked by callers at appropriate times, rather than something that tuplestore tries to do behind the scenes. Second, a read pointer that is marked as allowing backward scan no longer prevents truncation. This means that a read pointer marked as having BACKWARD but not REWIND capability can only safely read backwards as far as the oldest other read pointer. (The expected use pattern for this involves having another read pointer that serves as the truncation fencepost.)
2008-12-18Fix oversight in my recent patch to allow ExecMakeFunctionResult to handleTom Lane
materialize-mode set results. Since it now uses the ReturnSetInfo node to hold internal state, we need to be sure to set up the node even when the immediately called function doesn't return set (but does have a set-valued argument). Per report from Anupama Aherrao.
2008-12-13Remove pg_plan_queries()'s now-useless needSnapshot parameter. It's uselessTom Lane
in 8.3, too, but I'm not back-patching this change since it would break any extension modules that might be calling that function.
2008-12-01Ensure that the contents of a holdable cursor don't depend on out-of-lineTom Lane
toasted values, since those could get dropped once the cursor's transaction is over. Per bug #4553 from Andrew Gierth. Back-patch as far as 8.1. The bug actually exists back to 7.4 when holdable cursors were introduced, but this patch won't work before 8.1 without significant adjustments. Given the lack of field complaints, it doesn't seem worth the work (and risk of introducing new bugs) to try to make a patch for the older branches.
2008-11-30Clean up the API for DestReceiver objects by eliminating the assumptionTom Lane
that a Portal is a useful and sufficient additional argument for CreateDestReceiver --- it just isn't, in most cases. Instead formalize the approach of passing any needed parameters to the receiver separately. One unexpected benefit of this change is that we can declare typedef Portal in a less surprising location. This patch is just code rearrangement and doesn't change any functionality. I'll tackle the HOLD-cursor-vs-toast problem in a follow-on patch.
2008-11-27Fix minor memory leak introduced in recent SQL-functions hacking: theTom Lane
DestReceiver created during postquel_start needs to be destroyed during postquel_end. In a moment of brain fade I had assumed this would be taken care of by FreeQueryDesc, but it's not (and shouldn't be).
2008-11-19Some infrastructure changes for the upcoming auto-explain contrib module:Tom Lane
* Refactor explain.c slightly to export a convenient-to-use subroutine for printing EXPLAIN results. * Provide hooks for plugins to get control at ExecutorStart and ExecutorEnd as well as ExecutorRun. * Add some minimal support for tracking the total runtime of ExecutorRun. This code won't actually do anything unless a plugin prods it to. * Change the API of the DefineCustomXXXVariable functions to allow nonzero "flags" to be specified for a custom GUC variable. While at it, also make the "bootstrap" default value for custom GUCs be explicitly specified as a parameter to these functions. This is to eliminate confusion over where the default comes from, as has been expressed in the past by some users of the custom-variable facility. * Refactor GUC code a bit to ensure that a custom variable gets initialized to something valid (like its default value) even if the placeholder value was invalid.
2008-11-16Modify UPDATE/DELETE WHERE CURRENT OF to use the FOR UPDATE infrastructure toTom Lane
locate the target row, if the cursor was declared with FOR UPDATE or FOR SHARE. This approach is more flexible and reliable than digging through the plan tree; for instance it can cope with join cursors. But we still provide the old code for use with non-FOR-UPDATE cursors. Per gripe from Robert Haas.
2008-11-15Fix crash of xmlconcat(NULL)Peter Eisentraut
also backpatched to 8.3
2008-11-15Make SELECT FOR UPDATE/SHARE work on inheritance trees, by having the planTom Lane
return the tableoid as well as the ctid for any FOR UPDATE targets that have child tables. All child tables are listed in the ExecRowMark list, but the executor just skips the ones that didn't produce the current row. Curiously, this longstanding restriction doesn't seem to have been documented anywhere; so no doc changes.
2008-11-06Improve bulk-insert performance by keeping the current target buffer pinnedTom Lane
(but not locked, as that would risk deadlocks). Also, make it work in a small ring of buffers to avoid having bulk inserts trash the whole buffer arena. Robert Haas, after an idea of Simon Riggs'.
2008-11-02Remove all uses of the deprecated functions heap_formtuple, heap_modifytuple,Tom Lane
and heap_deformtuple in favor of the newer functions heap_form_tuple et al (which do the same things but use bool control flags instead of arbitrary char values). Eliminate the former duplicate coding of these functions, reducing the deprecated functions to mere wrappers around the newer ones. We can't get rid of them entirely because add-on modules probably still contain many instances of the old coding style. Kris Jurka
2008-10-31Simplify ExecutorRun's API and save some trivial number of cycles by havingTom Lane
it just return void instead of sometimes returning a TupleTableSlot. SQL functions don't need that anymore, and noplace else does either. Eliminating the return value also means one less hassle for the ExecutorRun hook functions that will be supported beginning in 8.4.