aboutsummaryrefslogtreecommitdiff
path: root/src/backend/optimizer/prep/prepqual.c
Commit message (Collapse)AuthorAge
* 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 improper uses of canonicalize_qual().Tom Lane2018-03-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | One of the things canonicalize_qual() does is to remove constant-NULL subexpressions of top-level AND/OR clauses. It does that on the assumption that what it's given is a top-level WHERE clause, so that NULL can be treated like FALSE. Although this is documented down inside a subroutine of canonicalize_qual(), it wasn't mentioned in the documentation of that function itself, and some callers hadn't gotten that memo. Notably, commit d007a9505 caused get_relation_constraints() to apply canonicalize_qual() to CHECK constraints. That allowed constraint exclusion to misoptimize situations in which a CHECK constraint had a provably-NULL subclause, as seen in the regression test case added here, in which a child table that should be scanned is not. (Although this thinko is ancient, the test case doesn't fail before 9.2, for reasons I've not bothered to track down in detail. There may be related cases that do fail before that.) More recently, commit f0e44751d added an independent bug by applying canonicalize_qual() to index expressions, which is even sillier since those might not even be boolean. If they are, though, I think this could lead to making incorrect index entries for affected index expressions in v10. I haven't attempted to prove that though. To fix, add an "is_check" parameter to canonicalize_qual() to specify whether it should assume WHERE or CHECK semantics, and make it perform NULL-elimination accordingly. Adjust the callers to apply the right semantics, or remove the call entirely in cases where it's not known that the expression has one or the other semantics. I also removed the call in some cases involving partition expressions, where it should be a no-op because such expressions should be canonical already ... and was a no-op, independently of whether it could in principle have done something, because it was being handed the qual in implicit-AND format which isn't what it expects. In HEAD, add an Assert to catch that type of mistake in future. This represents an API break for external callers of canonicalize_qual(). While that's intentional in HEAD to make such callers think about which case applies to them, it seems like something we probably wouldn't be thanked for in released branches. Hence, in released branches, the extra parameter is added to a new function canonicalize_qual_ext(), and canonicalize_qual() is a wrapper that retains its old behavior. Patch by me with suggestions from Dean Rasheed. Back-patch to all supported branches. Discussion: https://postgr.es/m/24475.1520635069@sss.pgh.pa.us
* Update copyright for 2018Bruce Momjian2018-01-02
| | | | Backpatch-through: certain files through 9.3
* Update copyright via script for 2017Bruce Momjian2017-01-03
|
* Update copyright for 2016Bruce Momjian2016-01-02
| | | | Backpatch certain files through 9.1
* Add parse location fields to NullTest and BooleanTest structs.Tom Lane2015-02-22
| | | | | | | | We did not need a location tag on NullTest or BooleanTest before, because no error messages referred directly to their locations. That's planned to change though, so add these fields in a separate housekeeping commit. Catversion bump because stored rules may change.
* Update copyright for 2015Bruce Momjian2015-01-06
| | | | Backpatch certain files through 9.0
* Avoid recursion when processing simple lists of AND'ed or OR'ed clauses.Tom Lane2014-06-16
| | | | | | | | | | | | | | | | | | | Since most of the system thinks AND and OR are N-argument expressions anyway, let's have the grammar generate a representation of that form when dealing with input like "x AND y AND z AND ...", rather than generating a deeply-nested binary tree that just has to be flattened later by the planner. This avoids stack overflow in parse analysis when dealing with queries having more than a few thousand such clauses; and in any case it removes some rather unsightly inconsistencies, since some parts of parse analysis were generating N-argument ANDs/ORs already. It's still possible to get a stack overflow with weirdly parenthesized input, such as "x AND (y AND (z AND ( ... )))", but such cases are not mainstream usage. The maximum depth of parenthesization is already limited by Bison's stack in such cases, anyway, so that the limit is probably fairly platform-independent. Patch originally by Gurjeet Singh, heavily revised by me
* 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.
* Improve planner to drop constant-NULL inputs of AND/OR where it's legal.Tom Lane2014-04-29
| | | | | | | | | | | | | | | | | | | In general we can't discard constant-NULL inputs, since they could change the result of the AND/OR to be NULL. But at top level of WHERE, we do not need to distinguish a NULL result from a FALSE result, so it's okay to treat NULL as FALSE and then simplify AND/OR accordingly. This is a very ancient oversight, but in 9.2 and later it can lead to failure to optimize queries that previous releases did optimize, as a result of more aggressive parameter substitution rules making it possible to reduce more subexpressions to NULL constants. This is the root cause of bug #10171 from Arnold Scheffler. We could alternatively have fixed that by teaching orclauses.c to ignore constant-NULL OR arms, but it seems better to get rid of them globally. I resisted the temptation to back-patch this change into all active branches, but it seems appropriate to back-patch as far as 9.2 so that there will not be performance regressions of the kind shown in this bug.
* 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.
* Update copyright notices for year 2012.Bruce Momjian2012-01-01
|
* pgindent run before PG 9.1 beta 1.Bruce Momjian2011-04-10
|
* Fix failure to propagate collation in negate_clause().Tom Lane2011-03-25
| | | | | Turns out it was this, and not so much plpgsql, that was at fault in Stefan Huehner's collation-error-in-a-trigger bug report of a couple weeks ago.
* Stamp copyrights for year 2011.Bruce Momjian2011-01-01
|
* 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
|
* Update copyright for the year 2010.Bruce Momjian2010-01-02
|
* Update copyright for 2009.Bruce Momjian2009-01-01
|
* Extend the parser location infrastructure to include a location field inTom Lane2008-08-28
| | | | | | | | | | | | | most node types used in expression trees (both before and after parse analysis). This allows us to place an error cursor in many situations where we formerly could not, because the information wasn't available beyond the very first level of parse analysis. There's a fair amount of work still to be done to persuade individual ereport() calls to actually include an error location, but this gets the initdb-forcing part of the work out of the way; and the situation is already markedly better than before for complaints about unimplementable implicit casts, such as CASE and UNION constructs with incompatible alternative data types. Per my proposal of a few days ago.
* Update copyrights in source tree to 2008.Bruce Momjian2008-01-01
|
* 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
|
* Remove 576 references of include files that were not needed.Bruce Momjian2006-07-14
|
* Update copyright for 2006. Update scripts.Bruce Momjian2006-03-05
|
* Teach push_nots() how to negate a ScalarArrayOpExpr. In passing, saveTom Lane2005-11-26
| | | | a palloc or two in the OpExpr case.
* Re-run pgindent, fixing a problem where comment lines after a blankBruce Momjian2005-11-22
| | | | | | | | | comment line where output as too long, and update typedefs for /lib directory. Also fix case where identifiers were used as variable names in the backend, but as typedefs in ecpg (favor the backend for indenting). Backpatch to 8.1.X.
* Standard pgindent run for 8.1.Bruce Momjian2005-10-15
|
* Fix an oversight I introduced on 2003-12-28: find_nots/push_nots shouldTom Lane2005-07-29
| | | | | | | | | continue to recurse after eliminating a NOT-below-a-NOT, since the contained subexpression will now be part of the top-level AND/OR structure and so deserves to be simplified. The real-world impact of this is probably minimal, since it'd require at least three levels of NOT to make a difference, but it's still a bug. Also remove some redundant tests for NULL subexpressions.
* 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.
* 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 ...
* Fix mistaken comment.Tom Lane2004-09-01
|
* Pgindent run for 8.0.Bruce Momjian2004-08-29
|
* Update copyright to 2004.Bruce Momjian2004-08-29
|
* Just about there on de-FastList-ification.Tom Lane2004-06-01
|
* 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.
* Instead of trying to force WHERE clauses into CNF or DNF normal form,Tom Lane2003-12-30
| | | | | | | | just look for common clauses that can be pulled out of ORs. Per recent discussion, extracting common clauses seems to be the only really useful effect of normalization, and if we do it explicitly then we can avoid cluttering the qual with partially-redundant duplicated expressions, which was an unpleasant side-effect of the old approach.
* 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.
* $Header: -> $PostgreSQL Changes ...PostgreSQL Daemon2003-11-29
|
* Another pgindent run with updated typedefs.Bruce Momjian2003-08-08
|
* Update copyrights to 2003.Bruce Momjian2003-08-04
|
* pgindent run.Bruce Momjian2003-08-04
|
* Fix some planner performance problems with large WHERE clauses, byTom Lane2003-05-28
| | | | | | | introducing new 'FastList' list-construction subroutines to use in hot spots. This avoids the O(N^2) behavior of repeated lappend's by keeping a tail pointer, while not changing behavior by reversing list order as the lcons() method would do.
* 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.
* Remove sys/types.h in files that include postgres.h, and hence c.h,Bruce Momjian2002-09-02
| | | | because c.h has sys/types.h.
* Update copyright to 2002.Bruce Momjian2002-06-20
|