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* Update copyright for 2006. Update scripts.Bruce Momjian2006-03-05
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* Standard pgindent run for 8.1.Bruce Momjian2005-10-15
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* 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.
* Revise handling of dropped columns in JOIN alias lists to avoid aTom Lane2005-06-03
| | | | | | | | | | | | | | | | | | | | | performance problem pointed out by phil@vodafone: to wit, we were spending O(N^2) time to check dropped-ness in an N-deep join tree, even in the case where the tree was freshly constructed and couldn't possibly mention any dropped columns. Instead of recursing in get_rte_attribute_is_dropped(), change the data structure definition: the joinaliasvars list of a JOIN RTE must have a NULL Const instead of a Var at any position that references a now-dropped column. This costs nothing during normal parse-rewrite-plan path, and instead we have a linear-time update to make when loading a stored rule that might contain now-dropped columns. While at it, move the responsibility for acquring locks on relations referenced by rules into this separate function (which I therefore chose to call AcquireRewriteLocks). This saves effort --- namely, duplicated lock grabs in parser and rewriter --- in the normal path at a cost of one extra non-locked heap_open() in the stored-rule path; seems a good tradeoff. A fringe benefit is that it is now *much* clearer that we acquire lock on relations referenced in rules before we make any rewriter decisions based on their properties. (I don't know of any bug of that ilk, but it wasn't exactly clear before.)
* 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 ...
* Pgindent run for 8.0.Bruce Momjian2004-08-29
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* Update copyright to 2004.Bruce Momjian2004-08-29
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* Repair some issues with column aliases and RowExpr construction in theTom Lane2004-08-19
| | | | | | | | | | | | presence of dropped columns. Document the already-presumed fact that eref aliases in relation RTEs are supposed to have entries for dropped columns; cause the user alias structs to have such entries too, so that there's always a one-to-one mapping to the underlying physical attnums. Adjust expandRTE() and related code to handle the case where a column that is part of a JOIN has been dropped. Generalize expandRTE()'s API so that it can be used in a couple of places that formerly rolled their own implementation of the same logic. Fix ruleutils.c to suppress display of aliases for columns that were dropped since the rule was made.
* Just about there on de-FastList-ification.Tom Lane2004-06-01
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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.
* Promote row expressions to full-fledged citizens of the expression syntax,Tom Lane2004-05-10
| | | | | | | | | | rather than allowing them only in a few special cases as before. In particular you can now pass a ROW() construct to a function that accepts a rowtype parameter. Internal generation of RowExprs fixes a number of corner cases that used to not work very well, such as referencing the whole-row result of a JOIN or subquery. This represents a further step in the work I started a month or so back to make rowtype values into first-class citizens.
* $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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* Implement outer-level aggregates to conform to the SQL spec, withTom Lane2003-06-06
| | | | | | | | extensions to support our historical behavior. An aggregate belongs to the closest query level of any of the variables in its argument, or the current query level if there are no variables (e.g., COUNT(*)). The implementation involves adding an agglevelsup field to Aggref, and treating outer aggregates like outer variables at planning time.
* 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.
* 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.
* Make flatten_join_alias_vars() do the right thing when expanding an aliasTom Lane2003-02-06
| | | | referenced from a subquery. Per example from Stefanos Harhalakis.
* IN clauses appearing at top level of WHERE can now be handled as joins.Tom Lane2003-01-20
| | | | | | | | | | There are two implementation techniques: the executor understands a new JOIN_IN jointype, which emits at most one matching row per left-hand row, or the result of the IN's sub-select can be fed through a DISTINCT filter and then joined as an ordinary relation. Along the way, some minor code cleanup in the optimizer; notably, break out most of the jointree-rearrangement preprocessing in planner.c and put it in a new file prep/prepjointree.c.
* Adjust API of expression_tree_mutator and query_tree_mutator toTom Lane2003-01-17
| | | | | | simplify callers. It turns out the common case is that the caller does want to recurse into sub-queries, so push support for that into these subroutines.
* Ooops, didn't cut-and-paste quite enough code from ResolveNew;Tom Lane2003-01-16
| | | | with result that flatten_join_alias_vars failed to descend into subselects.
* Allow merge and hash joins to occur on arbitrary expressions (anything notTom Lane2003-01-15
| | | | | | | | | | | | | | | | containing a volatile function), rather than only on 'Var = Var' clauses as before. This makes it practical to do flatten_join_alias_vars at the start of planning, which in turn eliminates a bunch of klugery inside the planner to deal with alias vars. As a free side effect, we now detect implied equality of non-Var expressions; for example in SELECT ... WHERE a.x = b.y and b.y = 42 we will deduce a.x = 42 and use that as a restriction qual on a. Also, we can remove the restriction introduced 12/5/02 to prevent pullup of subqueries whose targetlists contain sublinks. Still TODO: make statistical estimation routines in selfuncs.c and costsize.c smarter about expressions that are more complex than plain Vars. The need for this is considerably greater now that we have to be able to estimate the suitability of merge and hash join techniques on such expressions.
* Further tweaking of parsetree & plantree representation of SubLinks.Tom Lane2003-01-10
| | | | | | | Simplify SubLink by storing just a List of operator OIDs, instead of a list of incomplete OpExprs --- that was a bizarre and bulky choice, with no redeeming social value since we have to build new OpExprs anyway when forming the plan tree.
* Clean up plantree representation of SubPlan-s --- SubLink does not appearTom Lane2002-12-14
| | | | | | | | in the planned representation of a subplan at all any more, only SubPlan. This means subselect.c doesn't scribble on its input anymore, which seems like a good thing; and there are no longer three different possible interpretations of a SubLink. Simplify node naming and improve comments in primnodes.h. No change to stored rules, though.
* 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.
* Tweak querytree-dependency-extraction code so that columns of tablesTom Lane2002-09-11
| | | | | | | | | that are explicitly JOINed are not considered dependencies unless they are actually used in the query: mere presence in the joinaliasvars list of a JOIN RTE doesn't count as being used. The patch touches a number of files because I needed to generalize the API of query_tree_walker to support an additional flag bit, but the changes are otherwise quite small.
* pgindent run.Bruce Momjian2002-09-04
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* Update copyright to 2002.Bruce Momjian2002-06-20
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* Change set_plan_references and join_references to take an rtable ListTom Lane2002-05-18
| | | | | | | | rather than a Query node; this allows set_plan_references to recurse into subplans correctly. Fixes core dump on full outer joins in subplans. Also, invoke preprocess_expression on function RTEs' function expressions. This seems to fix the planner's problems with outer-level Vars in function RTEs.
* Second try at fixing join alias variables. Instead of attaching miscellaneousTom Lane2002-04-28
| | | | | | | | lists to join RTEs, attach a list of Vars and COALESCE expressions that will replace the join's alias variables during planning. This simplifies flatten_join_alias_vars while still making it easy to fix up varno references when transforming the query tree. Add regression test cases for interactions of subqueries with outer joins.
* Restructure representation of aggregate functions so that they have pg_procTom Lane2002-04-11
| | | | | | | | | | entries, per pghackers discussion. This fixes aggregates to live in namespaces, and also simplifies/speeds up lookup in parse_func.c. Also, add a 'proimplicit' flag to pg_proc that controls whether a type coercion function may be invoked implicitly, or only explicitly. The current settings of these flags are more permissive than I would like, but we will need to debate and refine the behavior; for now, I avoided breaking regression tests as much as I could.
* Restructure representation of join alias variables. An explicit JOINTom Lane2002-03-12
| | | | | | | | | | | | | | | now has an RTE of its own, and references to its outputs now are Vars referencing the JOIN RTE, rather than CASE-expressions. This allows reverse-listing in ruleutils.c to use the correct alias easily, rather than painfully reverse-engineering the alias namespace as it used to do. Also, nested FULL JOINs work correctly, because the result of the inner joins are simple Vars that the planner can cope with. This fixes a bug reported a couple times now, notably by Tatsuo on 18-Nov-01. The alias Vars are expanded into COALESCE expressions where needed at the very end of planning, rather than during parsing. Also, beginnings of support for showing plan qualifier expressions in EXPLAIN. There are probably still cases that need work. initdb forced due to change of stored-rule representation.
* pgindent run on all C files. Java run to follow. initdb/regressionBruce Momjian2001-10-25
| | | | tests pass.
* First cut at making indexscan cost estimates depend on correlationTom Lane2001-05-09
| | | | between index order and table order.
* Make the world safe for passing whole rows of views to functions. ThisTom Lane2001-04-18
| | | | already worked fine for whole rows of tables, but not so well for views...
* pgindent run. Make it all clean.Bruce Momjian2001-03-22
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* Change Copyright from PostgreSQL, Inc to PostgreSQL Global Development Group.Bruce Momjian2001-01-24
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* Reimplementation of UNION/INTERSECT/EXCEPT. INTERSECT/EXCEPT now meet theTom Lane2000-10-05
| | | | | | | | | | | SQL92 semantics, including support for ALL option. All three can be used in subqueries and views. DISTINCT and ORDER BY work now in views, too. This rewrite fixes many problems with cross-datatype UNIONs and INSERT/SELECT where the SELECT yields different datatypes than the INSERT needs. I did that by making UNION subqueries and SELECT in INSERT be treated like subselects-in-FROM, thereby allowing an extra level of targetlist where the datatype conversions can be inserted safely. INITDB NEEDED!
* First cut at full support for OUTER JOINs. There are still a few looseTom Lane2000-09-12
| | | | | ends to clean up (see my message of same date to pghackers), but mostly it works. INITDB REQUIRED!
* Ye-old pgindent run. Same 4-space tabs.Bruce Momjian2000-04-12
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* Add:Bruce Momjian2000-01-26
| | | | | | * Portions Copyright (c) 1996-2000, PostgreSQL, Inc to all files copyright Regents of Berkeley. Man, that's a lot of files.
* Clean up some mistakes in handling of uplevel Vars in planner.Tom Lane1999-08-26
| | | | | | | Most parts of the planner should ignore, or indeed never even see, uplevel Vars because they will be or have been replaced by Params. There were a couple of places that got it wrong though, probably my fault from recent changes...
* Further planner/optimizer cleanups. Move all set_tlist_referencesTom Lane1999-08-22
| | | | | | | | | | and fix_opids processing to a single recursive pass over the plan tree executed at the very tail end of planning, rather than haphazardly here and there at different places. Now that tlist Vars do not get modified until the very end, it's possible to get rid of the klugy var_equal and match_varid partial-matching routines, and just use plain equal() throughout the optimizer. This is a step towards allowing merge and hash joins to be done on expressions instead of only Vars ...
* Minor cleanups and code beautification; eliminate someTom Lane1999-08-10
| | | | routines that are now dead code.
* Remove unused #includes in *.c files.Bruce Momjian1999-07-15
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* Create a generic expression-tree-walker subroutine, whichTom Lane1999-06-19
| | | | | | will gradually replace all of the boilerplate tree-walk-recursion code that currently exists in O(N) slightly different forms in N subroutines. I've had it with adding missing cases to these subroutines...
* pgindent run over code.Bruce Momjian1999-05-25
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* Revise union_planner and associated routines to clean up breakageTom Lane1999-05-03
| | | | | from EXCEPT/HAVING patch. Cases involving nontrivial GROUP BY expressions now work again. Also, the code is at least somewhat better documented...