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* Refactor planner's header files.Tom Lane2019-01-29
| | | | | | | | | | | | | | | | | | | | | | | | Create a new header optimizer/optimizer.h, which exposes just the planner functions that can be used "at arm's length", without need to access Paths or the other planner-internal data structures defined in nodes/relation.h. This is intended to provide the whole planner API seen by most of the rest of the system; although FDWs still need to use additional stuff, and more thought is also needed about just what selfuncs.c should rely on. The main point of doing this now is to limit the amount of new #include baggage that will be needed by "planner support functions", which I expect to introduce later, and which will be in relevant datatype modules rather than anywhere near the planner. This commit just moves relevant declarations into optimizer.h from other header files (a couple of which go away because everything got moved), and adjusts #include lists to match. There's further cleanup that could be done if we want to decide that some stuff being exposed by optimizer.h doesn't belong in the planner at all, but I'll leave that for another day. Discussion: https://postgr.es/m/11460.1548706639@sss.pgh.pa.us
* Make some small planner API cleanups.Tom Lane2019-01-29
| | | | | | | | | | | | | | | | | | | | | | Move a few very simple node-creation and node-type-testing functions from the planner's clauses.c to nodes/makefuncs and nodes/nodeFuncs. There's nothing planner-specific about them, as evidenced by the number of other places that were using them. While at it, rename and_clause() etc to is_andclause() etc, to clarify that they are node-type-testing functions not node-creation functions. And use "static inline" implementations for the shortest ones. Also, modify flatten_join_alias_vars() and some subsidiary functions to take a Query not a PlannerInfo to define the join structure that Vars should be translated according to. They were only using the "parse" field of the PlannerInfo anyway, so this just requires removing one level of indirection. The advantage is that now parse_agg.c can use flatten_join_alias_vars() without the horrid kluge of creating an incomplete PlannerInfo, which will allow that file to be decoupled from relation.h in a subsequent patch. Discussion: https://postgr.es/m/11460.1548706639@sss.pgh.pa.us
* Update copyright for 2019Bruce Momjian2019-01-02
| | | | Backpatch-through: certain files through 9.4
* Fix oversight in commit b5415e3c2187ab304390524f5ae66b4bd2c58279.Tom Lane2018-12-31
| | | | | | | | | | | | | While rearranging code in tidpath.c, I overlooked the fact that we ought to check restriction_is_securely_promotable when trying to use a join clause as a TID qual. Since tideq itself is leakproof, this wouldn't really allow any interesting leak AFAICT, but it still seems like we had better check it. For consistency with the corresponding logic in indxpath.c, also check rinfo->pseudoconstant. I'm not sure right now that it's possible for that to be set in a join clause, but if it were, a match couldn't be made anyway.
* Support parameterized TidPaths.Tom Lane2018-12-30
| | | | | | | | | | | | | | | | | | | Up to now we've not worried much about joins where the join key is a relation's CTID column, reasoning that storing a table's CTIDs in some other table would be pretty useless. However, there are use-cases for this sort of query involving self-joins, so that argument doesn't really hold water. This patch allows generating plans for joins on CTID that use a nestloop with inner TidScan, similar to what we might do with an index on the join column. This is the most efficient way to join when the outer side of the nestloop is expected to yield relatively few rows. This change requires upgrading tidpath.c and the generated TidPaths to work with RestrictInfos instead of bare qual clauses, but that's long-postponed technical debt anyway. Discussion: https://postgr.es/m/17443.1545435266@sss.pgh.pa.us
* Update copyright for 2018Bruce Momjian2018-01-02
| | | | Backpatch-through: certain files through 9.3
* Improve RLS planning by marking individual quals with security levels.Tom Lane2017-01-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In an RLS query, we must ensure that security filter quals are evaluated before ordinary query quals, in case the latter contain "leaky" functions that could expose the contents of sensitive rows. The original implementation of RLS planning ensured this by pushing the scan of a secured table into a sub-query that it marked as a security-barrier view. Unfortunately this results in very inefficient plans in many cases, because the sub-query cannot be flattened and gets planned independently of the rest of the query. To fix, drop the use of sub-queries to enforce RLS qual order, and instead mark each qual (RestrictInfo) with a security_level field establishing its priority for evaluation. Quals must be evaluated in security_level order, except that "leakproof" quals can be allowed to go ahead of quals of lower security_level, if it's helpful to do so. This has to be enforced within the ordering of any one list of quals to be evaluated at a table scan node, and we also have to ensure that quals are not chosen for early evaluation (i.e., use as an index qual or TID scan qual) if they're not allowed to go ahead of other quals at the scan node. This is sufficient to fix the problem for RLS quals, since we only support RLS policies on simple tables and thus RLS quals will always exist at the table scan level only. Eventually these qual ordering rules should be enforced for join quals as well, which would permit improving planning for explicit security-barrier views; but that's a task for another patch. Note that FDWs would need to be aware of these rules --- and not, for example, send an insecure qual for remote execution --- but since we do not yet allow RLS policies on foreign tables, the case doesn't arise. This will need to be addressed before we can allow such policies. Patch by me, reviewed by Stephen Frost and Dean Rasheed. Discussion: https://postgr.es/m/8185.1477432701@sss.pgh.pa.us
* 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
* Update copyright for 2015Bruce Momjian2015-01-06
| | | | Backpatch certain files through 9.0
* pgindent run for 9.4Bruce Momjian2014-05-06
| | | | | This includes removing tabs after periods in C comments, which was applied to back branches, so this change should not effect backpatching.
* Update copyright for 2014Bruce Momjian2014-01-07
| | | | | Update all files in head, and files COPYRIGHT and legal.sgml in all back branches.
* Fix planner problems with LATERAL references in PlaceHolderVars.Tom Lane2013-08-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The planner largely failed to consider the possibility that a PlaceHolderVar's expression might contain a lateral reference to a Var coming from somewhere outside the PHV's syntactic scope. We had a previous report of a problem in this area, which I tried to fix in a quick-hack way in commit 4da6439bd8553059766011e2a42c6e39df08717f, but Antonin Houska pointed out that there were still some problems, and investigation turned up other issues. This patch largely reverts that commit in favor of a more thoroughly thought-through solution. The new theory is that a PHV's ph_eval_at level cannot be higher than its original syntactic level. If it contains lateral references, those don't change the ph_eval_at level, but rather they create a lateral-reference requirement for the ph_eval_at join relation. The code in joinpath.c needs to handle that. Another issue is that createplan.c wasn't handling nested PlaceHolderVars properly. In passing, push knowledge of lateral-reference checks for join clauses into join_clause_is_movable_to. This is mainly so that FDWs don't need to deal with it. This patch doesn't fix the original join-qual-placement problem reported by Jeremy Evans (and indeed, one of the new regression test cases shows the wrong answer because of that). But the PlaceHolderVar problems need to be fixed before that issue can be addressed, so committing this separately seems reasonable.
* Update copyrights for 2013Bruce Momjian2013-01-01
| | | | | Fully update git head, and update back branches in ./COPYRIGHT and legal.sgml files.
* Fix up planner infrastructure to support LATERAL properly.Tom Lane2012-08-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch takes care of a number of problems having to do with failure to choose valid join orders and incorrect handling of lateral references pulled up from subqueries. Notable changes: * Add a LateralJoinInfo data structure similar to SpecialJoinInfo, to represent join ordering constraints created by lateral references. (I first considered extending the SpecialJoinInfo structure, but the semantics are different enough that a separate data structure seems better.) Extend join_is_legal() and related functions to prevent trying to form unworkable joins, and to ensure that we will consider joins that satisfy lateral references even if the joins would be clauseless. * Fill in the infrastructure needed for the last few types of relation scan paths to support parameterization. We'd have wanted this eventually anyway, but it is necessary now because a relation that gets pulled up out of a UNION ALL subquery may acquire a reltargetlist containing lateral references, meaning that its paths *have* to be parameterized whether or not we have any code that can push join quals down into the scan. * Compute data about lateral references early in query_planner(), and save in RelOptInfo nodes, to avoid repetitive calculations later. * Assorted corner-case bug fixes. There's probably still some bugs left, but this is a lot closer to being real than it was before.
* 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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* 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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* Update copyright for 2009.Bruce Momjian2009-01-01
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* Move exprType(), exprTypmod(), expression_tree_walker(), and related routinesTom Lane2008-08-25
| | | | | | into nodes/nodeFuncs, so as to reduce wanton cross-subsystem #includes inside the backend. There's probably more that should be done along this line, but this is a start anyway.
* Restructure some header files a bit, in particular heapam.h, by removing someAlvaro Herrera2008-05-12
| | | | | | | | | | | | unnecessary #include lines in it. Also, move some tuple routine prototypes and macros to htup.h, which allows removal of heapam.h inclusion from some .c files. For this to work, a new header file access/sysattr.h needed to be created, initially containing attribute numbers of system columns, for pg_dump usage. While at it, make contrib ltree, intarray and hstore header files more consistent with our header style.
* Update copyrights in source tree to 2008.Bruce Momjian2008-01-01
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* Support UPDATE/DELETE WHERE CURRENT OF cursor_name, per SQL standard.Tom Lane2007-06-11
| | | | | | | | | Along the way, allow FOR UPDATE in non-WITH-HOLD cursors; there may once have been a reason to disallow that, but it seems to work now, and it's really rather necessary if you want to select a row via a cursor and then update it in a concurrent-safe fashion. Original patch by Arul Shaji, rather heavily editorialized by Tom Lane.
* 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 tid-scan code to make use of "ctid = ANY (array)" clauses, so thatTom Lane2005-11-26
| | | | | | | "ctid IN (list)" will still work after we convert IN to ScalarArrayOpExpr. Make some minor efficiency improvements while at it, such as ensuring that multiple TIDs are fetched in physical heap order. And fix EXPLAIN so that it shows what's really going on for a TID scan.
* Standard pgindent run for 8.1.Bruce Momjian2005-10-15
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* Clean up some very old and crufty code for TID scan planning. Not muchTom Lane2005-08-23
| | | | | functional difference really, but make use of stuff added to the planner since this code was touched last.
* 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.
* 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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* Use the new List API function names throughout the backend, and disable theNeil Conway2004-05-30
| | | | | list compatibility API by default. While doing this, I decided to keep the llast() macro around and introduce llast_int() and llast_oid() variants.
* Reimplement the linked list data structure used throughout the backend.Neil Conway2004-05-26
| | | | | | | | | | | | | | | | In the past, we used a 'Lispy' linked list implementation: a "list" was merely a pointer to the head node of the list. The problem with that design is that it makes lappend() and length() linear time. This patch fixes that problem (and others) by maintaining a count of the list length and a pointer to the tail node along with each head node pointer. A "list" is now a pointer to a structure containing some meta-data about the list; the head and tail pointers in that structure refer to ListCell structures that maintain the actual linked list of nodes. The function names of the list API have also been changed to, I hope, be more logically consistent. By default, the old function names are still available; they will be disabled-by-default once the rest of the tree has been updated to use the new API names.
* $Header: -> $PostgreSQL Changes ...PostgreSQL Daemon2003-11-29
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* Another pgindent run with updated typedefs.Bruce Momjian2003-08-08
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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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* 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.
* Phase 2 of read-only-plans project: restructure expression-tree nodesTom Lane2002-12-12
| | | | | | | | | so that all executable expression nodes inherit from a common supertype Expr. This is somewhat of an exercise in code purity rather than any real functional advance, but getting rid of the extra Oper or Func node formerly used in each operator or function call should provide at least a little space and speed improvement. initdb forced by changes in stored-rules representation.
* Restructure planning of nestloop inner indexscans so that the set of usableTom Lane2002-11-24
| | | | | | | | | | | joinclauses is determined accurately for each join. Formerly, the code only considered joinclauses that used all of the rels from the outer side of the join; thus for example FROM (a CROSS JOIN b) JOIN c ON (c.f1 = a.x AND c.f2 = b.y) could not exploit a two-column index on c(f1,f2), since neither of the qual clauses would be in the joininfo list it looked in. The new code does this correctly, and also is able to eliminate redundant clauses, thus fixing the problem noted 24-Oct-02 by Hans-Jürgen Schönig.
* Be careful to include postgres.h *before* any system headers, to ensureTom Lane2002-09-05
| | | | | | that the right flavors of largefile-related definitions are seen. Most of these changes are probably unnecessary, but better safe than sorry.
* Update copyright to 2002.Bruce Momjian2002-06-20
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* Further work on making use of new statistics in planner. Adjust APIsTom Lane2001-06-05
| | | | | | | | | of costsize.c routines to pass Query root, so that costsize can figure more things out by itself and not be so dependent on its callers to tell it everything it needs to know. Use selectivity of hash or merge clause to estimate number of tuples processed internally in these joins (this is more useful than it would've been before, since eqjoinsel is somewhat more accurate than before).
* Change Copyright from PostgreSQL, Inc to PostgreSQL Global Development Group.Bruce Momjian2001-01-24
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* Remove unused include files. Do not touch /port or includes used by defines.Bruce Momjian2000-05-30
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* Ye-old pgindent run. Same 4-space tabs.Bruce Momjian2000-04-12
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* New cost model for planning, incorporating a penalty for random pageTom Lane2000-02-15
| | | | | | | | | | | | | | | | | | | | | | | | | accesses versus sequential accesses, a (very crude) estimate of the effects of caching on random page accesses, and cost to evaluate WHERE- clause expressions. Export critical parameters for this model as SET variables. Also, create SET variables for the planner's enable flags (enable_seqscan, enable_indexscan, etc) so that these can be controlled more conveniently than via PGOPTIONS. Planner now estimates both startup cost (cost before retrieving first tuple) and total cost of each path, so it can optimize queries with LIMIT on a reasonable basis by interpolating between these costs. Same facility is a win for EXISTS(...) subqueries and some other cases. Redesign pathkey representation to achieve a major speedup in planning (I saw as much as 5X on a 10-way join); also minor changes in planner to reduce memory consumption by recycling discarded Path nodes and not constructing unnecessary lists. Minor cleanups to display more-plausible costs in some cases in EXPLAIN output. Initdb forced by change in interface to index cost estimation functions.
* Repair planning bugs caused by my misguided removal of restrictinfo linkTom Lane2000-02-07
| | | | | | | | | | | fields in JoinPaths --- turns out that we do need that after all :-(. Also, rearrange planner so that only one RelOptInfo is created for a particular set of joined base relations, no matter how many different subsets of relations it can be created from. This saves memory and processing time compared to the old method of making a bunch of RelOptInfos and then removing the duplicates. Clean up the jointree iteration logic; not sure if it's better, but I sure find it more readable and plausible now, particularly for the case of 'bushy plans'.