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* pgindent run for 9.5Bruce Momjian2015-05-23
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* Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE.Andres Freund2015-05-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
* Support flattening of empty-FROM subqueries and one-row VALUES tables.Tom Lane2015-03-11
| | | | | | | | | We can't handle this in the general case due to limitations of the planner's data representations; but we can allow it in many useful cases, by being careful to flatten only when we are pulling a single-row subquery up into a FROM (or, equivalently, inner JOIN) node that will still have at least one remaining relation child. Per discussion of an example from Kyotaro Horiguchi.
* Update copyright for 2015Bruce Momjian2015-01-06
| | | | Backpatch certain files through 9.0
* Fix some more problems with nested append relations.Tom Lane2014-10-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As of commit a87c72915 (which later got backpatched as far as 9.1), we're explicitly supporting the notion that append relations can be nested; this can occur when UNION ALL constructs are nested, or when a UNION ALL contains a table with inheritance children. Bug #11457 from Nelson Page, as well as an earlier report from Elvis Pranskevichus, showed that there were still nasty bugs associated with such cases: in particular the EquivalenceClass mechanism could try to generate "join" clauses connecting an appendrel child to some grandparent appendrel, which would result in assertion failures or bogus plans. Upon investigation I concluded that all current callers of find_childrel_appendrelinfo() need to be fixed to explicitly consider multiple levels of parent appendrels. The most complex fix was in processing of "broken" EquivalenceClasses, which are ECs for which we have been unable to generate all the derived equality clauses we would like to because of missing cross-type equality operators in the underlying btree operator family. That code path is more or less entirely untested by the regression tests to date, because no standard opfamilies have such holes in them. So I wrote a new regression test script to try to exercise it a bit, which turned out to be quite a worthwhile activity as it exposed existing bugs in all supported branches. The present patch is essentially the same as far back as 9.2, which is where parameterized paths were introduced. In 9.0 and 9.1, we only need to back-patch a small fragment of commit 5b7b5518d, which fixes failure to propagate out the original WHERE clauses when a broken EC contains constant members. (The regression test case results show that these older branches are noticeably stupider than 9.2+ in terms of the quality of the plans generated; but we don't really care about plan quality in such cases, only that the plan not be outright wrong. A more invasive fix in the older branches would not be a good idea anyway from a plan-stability standpoint.)
* Make security barrier views automatically updatableStephen Frost2014-04-12
| | | | | | | | | | | | | | | | | Views which are marked as security_barrier must have their quals applied before any user-defined quals are called, to prevent user-defined functions from being able to see rows which the security barrier view is intended to prevent them from seeing. Remove the restriction on security barrier views being automatically updatable by adding a new securityQuals list to the RTE structure which keeps track of the quals from security barrier views at each level, independently of the user-supplied quals. When RTEs are later discovered which have securityQuals populated, they are turned into subquery RTEs which are marked as security_barrier to prevent any user-supplied quals being pushed down (modulo LEAKPROOF quals). Dean Rasheed, reviewed by Craig Ringer, Simon Riggs, KaiGai Kohei
* 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.
* More fixes for planner's handling of LATERAL.Tom Lane2012-08-12
| | | | | | | | | | | | | | | | | | | | | | | | Re-allow subquery pullup for LATERAL subqueries, except when the subquery is below an outer join and contains lateral references to relations outside that outer join. If we pull up in such a case, we risk introducing lateral cross-references into outer joins' ON quals, which is something the code is entirely unprepared to cope with right now; and I'm not sure it'll ever be worth coping with. Support lateral refs in VALUES (this seems to be the only additional path type that needs such support as a consequence of re-allowing subquery pullup). Put in a slightly hacky fix for joinpath.c's refusal to consider parameterized join paths even when there cannot be any unparameterized ones. This was causing "could not devise a query plan for the given query" failures in queries involving more than two FROM items. Put in an even more hacky fix for distribute_qual_to_rels() being unhappy with join quals that contain references to rels outside their syntactic scope; which is to say, disable that test altogether. Need to think about how to preserve some sort of debugging cross-check here, while not expending more cycles than befits a debugging cross-check.
* Run pgindent on 9.2 source tree in preparation for first 9.3Bruce Momjian2012-06-10
| | | | commit-fest.
* Preserve column names in the execution-time tupledesc for a RowExpr.Tom Lane2012-02-14
| | | | | | | | | | | | | | | The hstore and json datatypes both have record-conversion functions that pay attention to column names in the composite values they're handed. We used to not worry about inserting correct field names into tuple descriptors generated at runtime, but given these examples it seems useful to do so. Observe the nicer-looking results in the regression tests whose results changed. catversion bump because there is a subtle change in requirements for stored rule parsetrees: RowExprs from ROW() constructs now have to include field names. Andrew Dunstan and Tom Lane
* Update copyright notices for year 2012.Bruce Momjian2012-01-01
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* Stamp copyrights for year 2011.Bruce Momjian2011-01-01
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* Use appendrel planning logic for top-level UNION ALL structures.Tom Lane2010-11-08
| | | | | | | | | | | | | Formerly, we could convert a UNION ALL structure inside a subquery-in-FROM into an appendrel, as a side effect of pulling up the subquery into its parent; but top-level UNION ALL always caused use of plan_set_operations(). That didn't matter too much because you got an Append-based plan either way. However, now that the appendrel code can do things with MergeAppend, it's worthwhile to hack up the top-level case so it also uses appendrels. This is a bit of a stopgap; but going much further than this will require a major rewrite of the planner's set-operations support, which I'm not prepared to undertake now. For the moment let's grab the low-hanging fruit.
* Improve the planner's simplification of NOT constructs.Tom Lane2010-10-10
| | | | | | | | | | | | | | | | | This patch merges the responsibility for NOT-flattening into eval_const_expressions' processing. It wasn't done that way originally because prepqual.c is far older than eval_const_expressions. But putting this work into eval_const_expressions saves one pass over the qual trees, and in fact saves even more than that because we can exploit the knowledge that the subexpressions have already been recursively simplified. Doing it this way also lets us do it uniformly over all expressions, whereas prepqual.c formerly just did it at top level to save cycles. That should improve the planner's ability to recognize logically-equivalent constructs. While at it, also add the ability to fold a NOT into BooleanTest and NullTest constructs (the latter only for the scalar-datatype case). Per discussion of bug #5702.
* Remove cvs keywords from all files.Magnus Hagander2010-09-20
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* Update copyright for the year 2010.Bruce Momjian2010-01-02
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* Re-implement EvalPlanQual processing to improve its performance and eliminateTom Lane2009-10-26
| | | | | | | | | | | | | | | | | | | | | | | | | a lot of strange behaviors that occurred in join cases. We now identify the "current" row for every joined relation in UPDATE, DELETE, and SELECT FOR UPDATE/SHARE queries. If an EvalPlanQual recheck is necessary, we jam the appropriate row into each scan node in the rechecking plan, forcing it to emit only that one row. The former behavior could rescan the whole of each joined relation for each recheck, which was terrible for performance, and what's much worse could result in duplicated output tuples. Also, the original implementation of EvalPlanQual could not re-use the recheck execution tree --- it had to go through a full executor init and shutdown for every row to be tested. To avoid this overhead, I've associated a special runtime Param with each LockRows or ModifyTable plan node, and arranged to make every scan node below such a node depend on that Param. Thus, by signaling a change in that Param, the EPQ machinery can just rescan the already-built test plan. This patch also adds a prohibition on set-returning functions in the targetlist of SELECT FOR UPDATE/SHARE. This is needed to avoid the duplicate-output-tuple problem. It seems fairly reasonable since the other restrictions on SELECT FOR UPDATE are meant to ensure that there is a unique correspondence between source tuples and result tuples, which an output SRF destroys as much as anything else does.
* Do some minor code refactoring in preparation for changing the APIs ofTom Lane2009-05-12
| | | | | | | | | | | | | | | | | find_inheritance_children() and find_all_inheritors(). I got annoyed that these are buried inside the planner but mostly used elsewhere. So, create a new file catalog/pg_inherits.c and put them there, along with a couple of other functions that search pg_inherits. The code that modifies pg_inherits is (still) in tablecmds.c --- it's kind of entangled with unrelated code that modifies pg_depend and other stuff, so pulling it out seemed like a bigger change than I wanted to make right now. But this file provides a natural home for it if anyone ever gets around to that. This commit just moves code around; it doesn't change anything, except I succumbed to the temptation to make a couple of trivial optimizations in typeInheritsFrom().
* Improve pull_up_subqueries logic so that it doesn't insert unnecessaryTom Lane2009-04-28
| | | | | | | PlaceHolderVar nodes in join quals appearing in or below the lowest outer join that could null the subquery being pulled up. This improves the planner's ability to recognize constant join quals, and probably helps with detection of common sort keys (equivalence classes) as well.
* Update copyright for 2009.Bruce Momjian2009-01-01
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* Get rid of adjust_appendrel_attr_needed(), which has been broken ever sinceTom Lane2008-11-11
| | | | | | | | | | | we extended the appendrel mechanism to support UNION ALL optimization. The reason nobody noticed was that we are not actually using attr_needed data for appendrel children; hence it seems more reasonable to rip it out than fix it. Back-patch to 8.2 because an Assert failure is possible in corner cases. Per examination of an example from Jim Nasby. In HEAD, also get rid of AppendRelInfo.col_mappings, which is quite inadequate to represent UNION ALL situations; depend entirely on translated_vars instead.
* Improve sublink pullup code to handle ANY/EXISTS sublinks that are at topTom Lane2008-08-17
| | | | | | | | | | | | | level of a JOIN/ON clause, not only at top level of WHERE. (However, we can't do this in an outer join's ON clause, unless the ANY/EXISTS refers only to the nullable side of the outer join, so that it can effectively be pushed down into the nullable side.) Per request from Kevin Grittner. In passing, fix a bug in the initial implementation of EXISTS pullup: it would Assert if the EXIST's WHERE clause used a join alias variable. Since we haven't yet flattened join aliases when this transformation happens, it's necessary to include join relids in the computed set of RHS relids.
* Implement SEMI and ANTI joins in the planner and executor. (Semijoins replaceTom Lane2008-08-14
| | | | | | | | | | | | | | the old JOIN_IN code, but antijoins are new functionality.) Teach the planner to convert appropriate EXISTS and NOT EXISTS subqueries into semi and anti joins respectively. Also, LEFT JOINs with suitable upper-level IS NULL filters are recognized as being anti joins. Unify the InClauseInfo and OuterJoinInfo infrastructure into "SpecialJoinInfo". With that change, it becomes possible to associate a SpecialJoinInfo with every join attempt, which permits some cleanup of join selectivity estimation. That needs to be taken much further than this patch does, but the next step is to change the API for oprjoin selectivity functions, which seems like material for a separate patch. So for the moment the output size estimates for semi and especially anti joins are quite bogus.
* Arrange to "inline" SQL functions that appear in a query's FROM clause,Tom Lane2008-03-18
| | | | | | | are declared to return set, and consist of just a single SELECT. We can replace the FROM-item with a sub-SELECT and then optimize much as if we were dealing with a view. Patch from Richard Rowell, cleaned up by me.
* Update copyrights in source tree to 2008.Bruce Momjian2008-01-01
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* Update CVS HEAD for 2007 copyright. Back branches are typically notBruce Momjian2007-01-05
| | | | back-stamped for this.
* pgindent run for 8.2.Bruce Momjian2006-10-04
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* Update copyright for 2006. Update scripts.Bruce Momjian2006-03-05
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* Teach planner to convert simple UNION ALL subqueries into append relations,Tom Lane2006-02-03
| | | | | | | | | thereby sharing code with the inheritance case. This puts the UNION-ALL-view approach to partitioned tables on par with inheritance, so far as constraint exclusion is concerned: it works either way. (Still need to update the docs to say so.) The definition of "simple UNION ALL" is a little simpler than I would like --- basically the union arms can only be SELECT * FROM foo --- but it's good enough for partitioned-table cases.
* Restructure planner's handling of inheritance. Rather than processingTom Lane2006-01-31
| | | | | | | | | | | | | inheritance trees on-the-fly, which pretty well constrained us to considering only one way of planning inheritance, expand inheritance sets during the planner prep phase, and build a side data structure that can be consulted later to find which RTEs are members of which inheritance sets. As proof of concept, use the data structure to plan joins against inheritance sets more efficiently: we can now use indexes on the set members in inner-indexscan joins. (The generated plans could be improved further, but it'll take some executor changes.) This data structure will also support handling UNION ALL subqueries in the same way as inheritance sets, but that aspect of it isn't finished yet.
* Teach planner how to rearrange join order for some classes of OUTER JOIN.Tom Lane2005-12-20
| | | | | | Per my recent proposal. I ended up basing the implementation on the existing mechanism for enforcing valid join orders of IN joins --- the rules for valid outer-join orders are somewhat similar.
* Standard pgindent run for 8.1.Bruce Momjian2005-10-15
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* If a LIMIT is applied to a UNION ALL query, plan each UNION arm asTom Lane2005-06-10
| | | | | | | if the limit were directly applied to it. This does not actually add a LIMIT plan node to the generated subqueries --- that would be useless overhead --- but it does cause the planner to prefer fast- start plans when the limit is small. After an idea from Phil Endecott.
* Remove planner's private fields from Query struct, and put them intoTom Lane2005-06-05
| | | | | | | | a new PlannerInfo struct, which is passed around instead of the bare Query in all the planning code. This commit is essentially just a code-beautification exercise, but it does open the door to making larger changes to the planner data structures without having to muck with the widely-known Query struct.
* Rethink the order of expression preprocessing: eval_const_expressionsTom Lane2005-03-28
| | | | | | | | | | really ought to run before canonicalize_qual, because it can now produce forms that canonicalize_qual knows how to improve (eg, NOT clauses). Also, because eval_const_expressions already knows about flattening nested ANDs and ORs into N-argument form, the initial flatten_andors pass in canonicalize_qual is now completely redundant and can be removed. This doesn't save a whole lot of code, but the time and palloc traffic eliminated is a useful gain on large expression trees.
* This patch moves some code for preprocessing FOR UPDATE fromNeil Conway2005-03-17
| | | | | | grouping_planner() to preprocess_targetlist(), according to a comment in grouping_planner(). I think the refactoring makes sense, and moves some extraneous details out of grouping_planner().
* 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 ...
* Clean up handling of inherited-table update queries, per bug reportTom Lane2004-10-02
| | | | | | | from Sebastian Böck. The fix involves being more consistent about when rangetable entries are copied or modified. Someday we really need to fix this stuff to not scribble on its input data structures in the first place...
* Update copyright to 2004.Bruce Momjian2004-08-29
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* Extend set-operation planning to keep track of the sort ordering inducedTom Lane2004-04-07
| | | | | | by the set operation, so that redundant sorts at higher levels can be avoided. This was foreseen a good while back, but not done. Per request from Karel Zak.
* Clean up the usage of canonicalize_qual(): in particular, be consistentTom Lane2003-12-28
| | | | | | | | | about whether it is applied before or after eval_const_expressions(). I believe there were some corner cases where the system would fail to recognize that a partial index is applicable because of the previous inconsistency. Store normal rather than 'implicit AND' representations of constraints and index predicates in the catalogs. initdb forced due to representation change of constraints/predicates.
* make sure the $Id tags are converted to $PostgreSQL as well ...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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* Adjust subquery qual pushdown rules so that we can push down a qualTom Lane2003-04-24
| | | | | | into a UNION that has some type coercions applied to the component queries, so long as the qual itself does not reference any columns that have such coercions. Per example from Jonathan Bartlett 24-Apr-03.
* Turns out new IN implementation has got some problems in an UPDATE orTom Lane2003-03-05
| | | | | DELETE with inherited target table. Fix it; add a regression test. Also, correct ancient misspelling of 'inherited'.
* Detect case where an outer join can be reduced to a plain inner joinTom Lane2003-02-09
| | | | | because there are WHERE clauses that will reject the null-extended rows. Per suggestion from Brandon Craig Rhodes, 19-Nov-02.
* Replace planner's representation of relation sets, per pghackers discussion.Tom Lane2003-02-08
| | | | | Instead of Lists of integers, we now store variable-length bitmap sets. This should be faster as well as less error-prone.
* Allow the planner to collapse explicit inner JOINs together, rather thanTom Lane2003-01-25
| | | | | | | | | necessarily following the JOIN syntax to develop the query plan. The old behavior is still available by setting GUC variable JOIN_COLLAPSE_LIMIT to 1. Also create a GUC variable FROM_COLLAPSE_LIMIT to control the similar decision about when to collapse sub-SELECT lists into their parent lists. (This behavior existed already, but the limit was always GEQO_THRESHOLD/2; now it's separately adjustable.)
generated by cgit v1.2.3 (git 2.25.1) at 2025-08-09 09:12:52 +0000