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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.
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.
2007-08-15Repair problems occurring when multiple RI updates have to be done to the sameTom Lane
row within one query: we were firing check triggers before all the updates were done, leading to bogus failures. Fix by making the triggers queued by an RI update go at the end of the outer query's trigger event list, thereby effectively making the processing "breadth-first". This was indeed how it worked pre-8.0, so the bug does not occur in the 7.x branches. Per report from Pavel Stehule.
2007-02-15Repair oversight in 8.2 change that improved the handling of "pseudoconstant"Tom Lane
WHERE clauses. createplan.c is now willing to stick a gating Result node almost anywhere in the plan tree, and in particular one can wind up directly underneath a MergeJoin node. This means it had better be willing to handle Mark/Restore. Fortunately, that's trivial in such cases, since we can just pass off the call to the input node (which the planner has previously ensured can handle Mark/Restore). Per report from Phil Frost.
2007-02-02Repair failure to check that a table is still compatible with a previouslyTom Lane
made query plan. Use of ALTER COLUMN TYPE creates a hazard for cached query plans: they could contain Vars that claim a column has a different type than it now has. Fix this by checking during plan startup that Vars at relation scan level match the current relation tuple descriptor. Since at that point we already have at least AccessShareLock, we can be sure the column type will not change underneath us later in the query. However, since a backend's locks do not conflict against itself, there is still a hole for an attacker to exploit: he could try to execute ALTER COLUMN TYPE while a query is in progress in the current backend. Seal that hole by rejecting ALTER TABLE whenever the target relation is already open in the current backend. This is a significant security hole: not only can one trivially crash the backend, but with appropriate misuse of pass-by-reference datatypes it is possible to read out arbitrary locations in the server process's memory, which could allow retrieving database content the user should not be able to see. Our thanks to Jeff Trout for the initial report. Security: CVE-2007-0556
2006-12-26Fix failure due to accessing an already-freed tuple descriptor in a planTom Lane
involving HashAggregate over SubqueryScan (this is the known case, there may well be more). The bug is only latent in releases before 8.2 since they didn't try to access tupletable slots' descriptors during ExecDropTupleTable. The least bogus fix seems to be to make subqueries share the parent query's memory context, so that tupdescs they create will have the same lifespan as those of the parent query. There are comments in the code envisioning going even further by not having a separate child EState at all, but that will require rethinking executor access to range tables, which I don't want to tackle right now. Per bug report from Jean-Pierre Pelletier.
2006-10-04pgindent run for 8.2.Bruce Momjian
2006-09-03Revert FETCH/MOVE int64 patch. Was using incorrect checks forBruce Momjian
fetch/move in scan.l.
2006-09-02Change FETCH/MOVE to use int8.Bruce Momjian
Dhanaraj M
2006-08-27Add new return codes SPI_OK_INSERT_RETURNING etc to the SPI API.Tom Lane
Fix all the standard PLs to be able to return tuples from FOO_RETURNING statements as well as utility statements that return tuples. Also, fix oversight that SPI_processed wasn't set for a utility statement returning tuples. Per recent discussion.
2006-08-12Add INSERT/UPDATE/DELETE RETURNING, with basic docs and regression tests.Tom Lane
plpgsql support to come later. Along the way, convert execMain's SELECT INTO support into a DestReceiver, in order to eliminate some ugly special cases. Jonah Harris and Tom Lane
2006-08-04Fix domain_in() bug exhibited by Darcy Buskermolen. The idea of an EStateTom Lane
that's shorter-lived than the expression state being evaluated in it really doesn't work :-( --- we end up with fn_extra caches getting deleted while still in use. Rather than abandon the notion of caching expression state across domain_in calls altogether, I chose to make domain_in a bit cozier with ExprContext. All we really need for evaluating variable-free expressions is an ExprContext, not an EState, so I invented the notion of a "standalone" ExprContext. domain_in can prevent resource leakages by doing a ReScanExprContext on this rather than having to free it entirely; so we can make the ExprContext have the same lifespan (and particularly the same per_query memory context) as the expression state structs.
2006-08-02Add support for multi-row VALUES clauses as part of INSERT statementsJoe Conway
(e.g. "INSERT ... VALUES (...), (...), ...") and elsewhere as allowed by the spec. (e.g. similar to a FROM clause subselect). initdb required. Joe Conway and Tom Lane.
2006-07-13More include file adjustments.Bruce Momjian
2006-07-13More include file adjustments.Bruce Momjian
2006-07-13Allow include files to compile own their own.Bruce Momjian
Strip unused include files out unused include files, and add needed includes to C files. The next step is to remove unused include files in C files.
2006-07-11Alphabetically order reference to include files, "S"-"Z".Bruce Momjian
2006-07-11Sort reference of include files, "A" - "F".Bruce Momjian
2006-06-27Convert hash join code to use MinimalTuple format in tuple hash tableTom Lane
and batch files. Should reduce memory and I/O demands for such joins.
2006-06-27Create infrastructure for 'MinimalTuple' representation of in-memoryTom Lane
tuples with less header overhead than a regular HeapTuple, per my recent proposal. Teach TupleTableSlot code how to deal with these. As proof of concept, change tuplestore.c to store MinimalTuples instead of HeapTuples. Future patches will expand the concept to other places where it is useful.
2006-06-16Fix problems with cached tuple descriptors disappearing while still in useTom Lane
by creating a reference-count mechanism, similar to what we did a long time ago for catcache entries. The back branches have an ugly solution involving lots of extra copies, but this way is more efficient. Reference counting is only applied to tupdescs that are actually in caches --- there seems no need to use it for tupdescs that are generated in the executor, since they'll go away during plan shutdown by virtue of being in the per-query memory context. Neil Conway and Tom Lane
2006-06-09Revert sampling patch for EXPLAIN ANALYZE; it turns out to be too unreliableTom Lane
because node timing is much less predictable than the patch expects. I kept the API change for InstrStopNode, however.
2006-05-30Code review for EXPLAIN patch. Fix some typos, make it behave sanelyTom Lane
across multiple loops, get rid of the shaky assumption that exactly one tuple is returned per node iteration.
2006-05-30Make EXPLAIN sampling smarter, to avoid excessive sampling delay.Bruce Momjian
Martijn van Oosterhout
2006-05-23Remove CXT_printf/CXT1_printf macros. If anyone had found them to be ofTom Lane
any use in the past many years, we'd have made some effort to include them in all executor node types; but in fact they were only in nodeAppend.c and nodeIndexscan.c, up until I copied nodeIndexscan.c's occurrence into the new bitmap node types. Remove some other unused macros in execdebug.h, too. Some day the whole header probably ought to go away in favor of better-designed facilities.
2006-03-05Update copyright for 2006. Update scripts.Bruce Momjian
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
2006-01-25Allow row comparisons to be used as indexscan qualifications.Tom Lane
This completes the project to upgrade our handling of row comparisons.
2006-01-12Repair "Halloween problem" in EvalPlanQual: a tuple that's been inserted byTom Lane
our own command (or more generally, xmin = our xact and cmin >= current command ID) should not be seen as good. Else we may try to update rows we already updated. This error was inserted last August while fixing the even bigger problem that the old coding wouldn't see *any* tuples inserted by our own transaction as good. Per report from Euler Taveira de Oliveira.
2005-12-03Tweak indexscan machinery to avoid taking an AccessShareLock on an indexTom Lane
if we already have a stronger lock due to the index's table being the update target table of the query. Same optimization I applied earlier at the table level. There doesn't seem to be much interest in the more radical idea of not locking indexes at all, so do what we can ...
2005-12-02Adjust scan plan nodes to avoid getting an extra AccessShareLock on aTom Lane
relation if it's already been locked by execMain.c as either a result relation or a FOR UPDATE/SHARE relation. This avoids an extra trip to the shared lock manager state. Per my suggestion yesterday.
2005-11-25Teach planner and executor to handle ScalarArrayOpExpr as an indexableTom Lane
qualification when the underlying operator is indexable and useOr is true. That is, indexkey op ANY (ARRAY[...]) is effectively translated into an OR combination of one indexscan for each array element. This only works for bitmap index scans, of course, since regular indexscans no longer support OR'ing of scans. There are still some loose ends to clean up before changing 'x IN (list)' to translate as a ScalarArrayOpExpr; for instance predtest.c ought to be taught about it. But this gets the basic functionality in place.
2005-11-23Get rid of ExecAssignResultTypeFromOuterPlan() and make all plan node typesTom Lane
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.
2005-10-15Standard pgindent run for 8.1.Bruce Momjian
2005-10-01_SPI_execute_plan failed to return result tuple table to caller inTom Lane
the ProcessUtility case, resulting in an intratransaction memory leak if a utility command actually did return any tuples, as reported by Dmitry Karasik. Fix this and also make the behavior more consistent for cases involving nested SPI operations and multiple query trees, by ensuring that we store the state locally until it is ready to be returned to the caller.
2005-08-20Repair problems with VACUUM destroying t_ctid chains too soon, and withTom Lane
insufficient paranoia in code that follows t_ctid links. (We must do both because even with VACUUM doing it properly, the intermediate state with a dangling t_ctid link is visible concurrently during lazy VACUUM, and could be seen afterwards if either type of VACUUM crashes partway through.) Also try to improve documentation about what's going on. Patch is a bit bulky because passing the XMAX information around required changing the APIs of some low-level heapam.c routines, but it's not conceptually very complicated. Per trouble report from Teodor and subsequent analysis. This needs to be back-patched, but I'll do that after 8.1 beta is out.
2005-05-13Revise nodeMergejoin in light of example provided by Guillaume Smet.Tom Lane
When one side of the join has a NULL, we don't want to uselessly try to match it against every remaining tuple of the other side. While at it, rewrite the comparison machinery to avoid multiple evaluations of the left and right input expressions and to use a btree comparator where available, instead of double operator calls. Also revise the state machine to eliminate redundant comparisons and hopefully make it more readable too.
2005-05-02Change SPI functions to use a `long' when specifying the number of tuplesNeil Conway
to produce when running the executor. This is consistent with the internal executor APIs (such as ExecutorRun), which also use a long for this purpose. It also allows FETCH_ALL to be passed -- since FETCH_ALL is defined as LONG_MAX, this wouldn't have worked on platforms where int and long are of different sizes. Per report from Tzahi Fadida.
2005-04-25Remove support for OR'd indexscans internal to a single IndexScan planTom Lane
node, as this behavior is now better done as a bitmap OR indexscan. This allows considerable simplification in nodeIndexscan.c itself as well as several planner modules concerned with indexscan plan generation. Also we can improve the sharing of code between regular and bitmap indexscans, since they are now working with nigh-identical Plan nodes.
2005-04-19Create executor and planner-backend support for decoupled heap and indexTom Lane
scans, using in-memory tuple ID bitmaps as the intermediary. The planner frontend (path creation and cost estimation) is not there yet, so none of this code can be executed. I have tested it using some hacked planner code that is far too ugly to see the light of day, however. Committing now so that the bulk of the infrastructure changes go in before the tree drifts under me.
2005-04-16Create a new 'MultiExecProcNode' call API for plan nodes that don'tTom Lane
return just a single tuple at a time. Currently the only such node type is Hash, but I expect we will soon have indexscans that can return tuple bitmaps. A side benefit is that EXPLAIN ANALYZE now shows the correct tuple count for a Hash node.
2005-03-31First phase of OUT-parameters project. We can now define and use SQLTom Lane
functions with OUT parameters. The various PLs still need work, as does pg_dump. Rudimentary docs and regression tests included.
2005-03-29Add SPI_getnspname(), including documentation.Neil Conway
2005-03-25Improve EXPLAIN ANALYZE to show the time spent in each trigger whenTom Lane
executing a statement that fires triggers. Formerly this time was included in "Total runtime" but not otherwise accounted for. As a side benefit, we avoid re-opening relations when firing non-deferred AFTER triggers, because the trigger code can re-use the main executor's ResultRelInfo data structure.
2005-03-20On Windows, use QueryPerformanceCounter instead of gettimeofday forTom Lane
EXPLAIN ANALYZE instrumentation. Magnus Hagander
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.
2005-03-14Avoid O(N^2) overhead in repeated nocachegetattr calls when columns ofTom Lane
a tuple are being accessed via ExecEvalVar and the attcacheoff shortcut isn't usable (due to nulls and/or varlena columns). To do this, cache Datums extracted from a tuple in the associated TupleTableSlot. Also some code cleanup in and around the TupleTable handling. Atsushi Ogawa with some kibitzing by Tom Lane.
2005-03-06Revise hash join code so that we can increase the number of batchesTom Lane
on-the-fly, and thereby avoid blowing out memory when the planner has underestimated the hash table size. Hash join will now obey the work_mem limit with some faithfulness. Per my recent proposal (hash aggregate part isn't done yet though).
2005-01-28Improve planner's estimation of the space needed for HashAgg plans:Tom Lane
look at the actual aggregate transition datatypes and the actual overhead needed by nodeAgg.c, instead of using pessimistic round numbers. Per a discussion with Michael Tiemann.
2005-01-01Update copyrights that were missed.Bruce Momjian