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* Move ExecProcNode from dispatch to function pointer based model.Andres Freund2017-07-30
| | | | | | | | | | | | | | | | | | | | | | This allows us to add stack-depth checks the first time an executor node is called, and skip that overhead on following calls. Additionally it yields a nice speedup. While it'd probably have been a good idea to have that check all along, it has become more important after the new expression evaluation framework in b8d7f053c5c2bf2a7e - there's no stack depth check in common paths anymore now. We previously relied on ExecEvalExpr() being executed somewhere. We should move towards that model for further routines, but as this is required for v10, it seems better to only do the necessary (which already is quite large). Author: Andres Freund, Tom Lane Reported-By: Julien Rouhaud Discussion: https://postgr.es/m/22833.1490390175@sss.pgh.pa.us https://postgr.es/m/b0af9eaa-130c-60d0-9e4e-7a135b1e0c76@dalibo.com
* Move interrupt checking from ExecProcNode() to executor nodes.Andres Freund2017-07-30
| | | | | | | | | | | | | | | | | In a followup commit ExecProcNode(), and especially the large switch it contains, will largely be replaced by a function pointer directly to the correct node. The node functions will then get invoked by a thin inline function wrapper. To avoid having to include miscadmin.h in headers - CHECK_FOR_INTERRUPTS() - move the interrupt checks into the individual executor routines. While looking through all executor nodes, I noticed a number of arguably missing interrupt checks, add these too. Author: Andres Freund, Tom Lane Reviewed-By: Tom Lane Discussion: https://postgr.es/m/22833.1490390175@sss.pgh.pa.us
* Faster expression evaluation and targetlist projection.Andres Freund2017-03-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This replaces the old, recursive tree-walk based evaluation, with non-recursive, opcode dispatch based, expression evaluation. Projection is now implemented as part of expression evaluation. This both leads to significant performance improvements, and makes future just-in-time compilation of expressions easier. The speed gains primarily come from: - non-recursive implementation reduces stack usage / overhead - simple sub-expressions are implemented with a single jump, without function calls - sharing some state between different sub-expressions - reduced amount of indirect/hard to predict memory accesses by laying out operation metadata sequentially; including the avoidance of nearly all of the previously used linked lists - more code has been moved to expression initialization, avoiding constant re-checks at evaluation time Future just-in-time compilation (JIT) has become easier, as demonstrated by released patches intended to be merged in a later release, for primarily two reasons: Firstly, due to a stricter split between expression initialization and evaluation, less code has to be handled by the JIT. Secondly, due to the non-recursive nature of the generated "instructions", less performance-critical code-paths can easily be shared between interpreted and compiled evaluation. The new framework allows for significant future optimizations. E.g.: - basic infrastructure for to later reduce the per executor-startup overhead of expression evaluation, by caching state in prepared statements. That'd be helpful in OLTPish scenarios where initialization overhead is measurable. - optimizing the generated "code". A number of proposals for potential work has already been made. - optimizing the interpreter. Similarly a number of proposals have been made here too. The move of logic into the expression initialization step leads to some backward-incompatible changes: - Function permission checks are now done during expression initialization, whereas previously they were done during execution. In edge cases this can lead to errors being raised that previously wouldn't have been, e.g. a NULL array being coerced to a different array type previously didn't perform checks. - The set of domain constraints to be checked, is now evaluated once during expression initialization, previously it was re-built every time a domain check was evaluated. For normal queries this doesn't change much, but e.g. for plpgsql functions, which caches ExprStates, the old set could stick around longer. The behavior around might still change. Author: Andres Freund, with significant changes by Tom Lane, changes by Heikki Linnakangas Reviewed-By: Tom Lane, Heikki Linnakangas Discussion: https://postgr.es/m/20161206034955.bh33paeralxbtluv@alap3.anarazel.de
* Remove obsoleted code relating to targetlist SRF evaluation.Andres Freund2017-01-19
| | | | | | | | | | | | | Since 69f4b9c plain expression evaluation (and thus normal projection) can't return sets of tuples anymore. Thus remove code dealing with that possibility. This will require adjustments in external code using ExecEvalExpr()/ExecProject() - that should neither be hard nor very common. Author: Andres Freund and Tom Lane Discussion: https://postgr.es/m/20160822214023.aaxz5l4igypowyri@alap3.anarazel.de
* Update copyright via script for 2017Bruce Momjian2017-01-03
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* Update copyright for 2016Bruce Momjian2016-01-02
| | | | Backpatch certain files through 9.1
* pgindent run for 9.5Bruce Momjian2015-05-23
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* Use outerPlanState macro instead of referring to leffttree.Robert Haas2015-05-04
| | | | | | | This makes the executor code more consistent. It also removes an apparently superfluous NULL test in nodeGroup.c. Qingqing Zhou, reviewed by Tom Lane, and further revised by me.
* Update copyright for 2015Bruce Momjian2015-01-06
| | | | Backpatch certain files through 9.0
* Update copyright for 2014Bruce Momjian2014-01-07
| | | | | Update all files in head, and files COPYRIGHT and legal.sgml in all back branches.
* Update copyrights for 2013Bruce Momjian2013-01-01
| | | | | Fully update git head, and update back branches in ./COPYRIGHT and legal.sgml files.
* Remove unreachable codePeter Eisentraut2012-07-16
| | | | | | | The Solaris Studio compiler warns about these instances, unlike more mainstream compilers such as gcc. But manual inspection showed that the code is clearly not reachable, and we hope no worthy compiler will complain about removing this code.
* Update copyright notices for year 2012.Bruce Momjian2012-01-01
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* Make EXPLAIN ANALYZE report the numbers of rows rejected by filter steps.Tom Lane2011-09-22
| | | | | | | | | | | | | | | This provides information about the numbers of tuples that were visited but not returned by table scans, as well as the numbers of join tuples that were considered and discarded within a join plan node. There is still some discussion going on about the best way to report counts for outer-join situations, but I think most of what's in the patch would not change if we revise that, so I'm going to go ahead and commit it as-is. Documentation changes to follow (they weren't in the submitted patch either). Marko Tiikkaja, reviewed by Marc Cousin, somewhat revised by Tom
* Stamp copyrights for year 2011.Bruce Momjian2011-01-01
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* Remove cvs keywords from all files.Magnus Hagander2010-09-20
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* Make NestLoop plan nodes pass outer-relation variables into their innerTom Lane2010-07-12
| | | | | | | | | | | | relation using the general PARAM_EXEC executor parameter mechanism, rather than the ad-hoc kluge of passing the outer tuple down through ExecReScan. The previous method was hard to understand and could never be extended to handle parameters coming from multiple join levels. This patch doesn't change the set of possible plans nor have any significant performance effect, but it's necessary infrastructure for future generalization of the concept of an inner indexscan plan. ExecReScan's second parameter is now unused, so it's removed.
* Update copyright for the year 2010.Bruce Momjian2010-01-02
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* Remove no-longer-needed ExecCountSlots infrastructure.Tom Lane2009-09-27
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* Revert DTrace patch from Robert LorBruce Momjian2009-04-02
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* Add support for additional DTrace probes.Bruce Momjian2009-04-02
| | | | Robert Lor
* Update copyright for 2009.Bruce Momjian2009-01-01
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* Fix an oversight in two different recent patches: nodes that support SRFsTom Lane2008-10-23
| | | | | | in their targetlists had better reset ps_TupFromTlist during ReScan calls. There's no need to back-patch here since nodeAgg and nodeGroup didn't even pretend to support SRFs in prior releases.
* Support set-returning functions in the target lists of Agg and Group planTom Lane2008-09-08
| | | | | | nodes. This is a pretty ugly feature but since we don't yet have a plausible substitute, we'd better support it everywhere. Per gripe from Jeff Davis.
* Update copyrights in source tree to 2008.Bruce Momjian2008-01-01
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* Change Agg and Group nodes so that Vars contained in their targetlistsTom Lane2007-02-22
| | | | | | | and quals have varno OUTER, rather than zero, to indicate a reference to an output of their lefttree subplan. This is consistent with the way that every other upper-level node type does it, and allows some simplifications in setrefs.c and EXPLAIN.
* Repair failure to check that a table is still compatible with a previouslyTom Lane2007-02-02
| | | | | | | | | | | | | | | | | | | | | | 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
* Change the planner-to-executor API so that the planner tells the executorTom Lane2007-01-10
| | | | | | | | | | | | | | | | which comparison operators to use for plan nodes involving tuple comparison (Agg, Group, Unique, SetOp). Formerly the executor looked up the default equality operator for the datatype, which was really pretty shaky, since it's possible that the data being fed to the node is sorted according to some nondefault operator class that could have an incompatible idea of equality. The planner knows what it has sorted by and therefore can provide the right equality operator to use. Also, this change moves a couple of catalog lookups out of the executor and into the planner, which should help startup time for pre-planned queries by some small amount. Modify the planner to remove some other cavalier assumptions about always being able to use the default operators. Also add "nulls first/last" info to the Plan node for a mergejoin --- neither the executor nor the planner can cope yet, but at least the API is in place.
* Update CVS HEAD for 2007 copyright. Back branches are typically notBruce Momjian2007-01-05
| | | | back-stamped for this.
* Remove 576 references of include files that were not needed.Bruce Momjian2006-07-14
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* 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
* 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.
* Make the behavior of HAVING without GROUP BY conform to the SQL spec.Tom Lane2005-03-10
| | | | | | | | | 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.
* 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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* Fix wrong/misleading comments, be more consistent about where to callTom Lane2003-01-12
| | | | ExecAssignResultTypeFromTL().
* Create a new file executor/execGrouping.c to centralize utility routinesTom Lane2003-01-10
| | | | shared by nodeGroup, nodeAgg, and soon nodeSubplan.
* 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.
* Tighten selection of equality and ordering operators for groupingTom Lane2002-11-29
| | | | | | | 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.
* Phase 2 of hashed-aggregation project. nodeAgg.c now knows how to doTom Lane2002-11-06
| | | | hashed aggregation, but there's not yet planner support for it.
* First phase of implementing hash-based grouping/aggregation. An AGG planTom Lane2002-11-06
| | | | | | | | | | | | | 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.
* Update copyright to 2002.Bruce Momjian2002-06-20
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* Get rid of the last few uses of typeidTypeName() rather thanTom Lane2002-05-17
| | | | format_type_be() in error messages.
* Operators live in namespaces. CREATE/DROP/COMMENT ON OPERATOR takeTom Lane2002-04-16
| | | | | | | | | | 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 >.