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2002-01-03Shouldn't try to copy null datums with datumCopy.Tom Lane
2001-12-10Suppress subquery pullup and pushdown when the subquery has anyTom Lane
set-returning functions in its target list. This ensures that we won't rewrite the query in a way that places set-returning functions into quals (WHERE clauses). Cf. bug reports from Joe Conway.
2001-11-05New pgindent run with fixes suggested by Tom. Patch manually reviewed,Bruce Momjian
initdb/regression tests pass.
2001-10-30Fix problems with subselects used in GROUP BY expressions, per gripeTom Lane
from Philip Warner. Side effect of change is that GROUP BY expressions will not be re-evaluated at multiple plan levels anymore, whereas this sometimes happened with old code.
2001-10-25pgindent run on all C files. Java run to follow. initdb/regressionBruce Momjian
tests pass.
2001-10-18Extend code that deduces implied equality clauses to detect whether aTom Lane
clause being added to a particular restriction-clause list is redundant with those already in the list. This avoids useless work at runtime, and (perhaps more importantly) keeps the selectivity estimation routines from generating too-small estimates of numbers of output rows. Also some minor improvements in OPTIMIZER_DEBUG displays.
2001-08-21Restructure pg_opclass, pg_amop, and pg_amproc per previous discussions inTom Lane
pgsql-hackers. pg_opclass now has a row for each opclass supported by each index AM, not a row for each opclass name. This allows pg_opclass to show directly whether an AM supports an opclass, and furthermore makes it possible to store additional information about an opclass that might be AM-dependent. pg_opclass and pg_amop now store "lossy" and "haskeytype" information that we previously expected the user to remember to provide in CREATE INDEX commands. Lossiness is no longer an index-level property, but is associated with the use of a particular operator in a particular index opclass. Along the way, IndexSupportInitialize now uses the syscaches to retrieve pg_amop and pg_amproc entries. I find this reduces backend launch time by about ten percent, at the cost of a couple more special cases in catcache.c's IndexScanOK. Initial work by Oleg Bartunov and Teodor Sigaev, further hacking by Tom Lane. initdb forced.
2001-07-31Further thought shows that has_distinct_on_clause() needs to take muchTom Lane
more care with resjunk tlist entries than it was doing. The original coding ignored resjunk entries entirely, but a resjunk entry that is in either the distinctClause or sortClause lists indicates that DISTINCT ON was used. It's important for ruleutils.c to get this right, else we may dump views using DISTINCT ON incorrectly.
2001-07-31Fix optimizer to not try to push WHERE clauses down into a sub-SELECT thatTom Lane
has a DISTINCT ON clause, per bug report from Anthony Wood. While at it, improve the DISTINCT-ON-clause recognizer routine to not be fooled by out- of-order DISTINCT lists.
2001-07-16Partial indexes work again, courtesy of Martijn van Oosterhout.Tom Lane
Note: I didn't force an initdb, figuring that one today was enough. However, there is a new function in pg_proc.h, and pg_dump won't be able to dump partial indexes until you add that function.
2001-07-15Restructure index AM interface for index building and index tuple deletion,Tom Lane
per previous discussion on pghackers. Most of the duplicate code in different AMs' ambuild routines has been moved out to a common routine in index.c; this means that all index types now do the right things about inserting recently-dead tuples, etc. (I also removed support for EXTEND INDEX in the ambuild routines, since that's about to go away anyway, and it cluttered the code a lot.) The retail indextuple deletion routines have been replaced by a "bulk delete" routine in which the indexscan is inside the access method. I haven't pushed this change as far as it should go yet, but it should allow considerable simplification of the internal bookkeeping for deletions. Also, add flag columns to pg_am to eliminate various hardcoded tests on AM OIDs, and remove unused pg_am columns. Fix rtree and gist index types to not attempt to store NULLs; before this, gist usually crashed, while rtree managed not to crash but computed wacko bounding boxes for NULL entries (which might have had something to do with the performance problems we've heard about occasionally). Add AtEOXact routines to hash, rtree, and gist, all of which have static state that needs to be reset after an error. We discovered this need long ago for btree, but missed the other guys. Oh, one more thing: concurrent VACUUM is now the default.
2001-06-19Add IS UNKNOWN, IS NOT UNKNOWN boolean tests, fix the existing booleanTom Lane
tests to return the correct results per SQL9x when given NULL inputs. Reimplement these tests as well as IS [NOT] NULL to have their own expression node types, instead of depending on special functions. From Joe Conway, with a little help from Tom Lane.
2001-06-05Further work on making use of new statistics in planner. Adjust APIsTom Lane
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).
2001-05-20Modify optimizer data structures so that IndexOptInfo lists built forTom Lane
create_index_paths are not immediately discarded, but are available for subsequent planner work. This allows avoiding redundant syscache lookups in several places. Change interface to operator selectivity estimation procedures to allow faster and more flexible estimation. Initdb forced due to change of pg_proc entries for selectivity functions!
2001-05-09First cut at making indexscan cost estimates depend on correlationTom Lane
between index order and table order.
2001-05-07Rewrite of planner statistics-gathering code. ANALYZE is now available asTom Lane
a separate statement (though it can still be invoked as part of VACUUM, too). pg_statistic redesigned to be more flexible about what statistics are stored. ANALYZE now collects a list of several of the most common values, not just one, plus a histogram (not just the min and max values). Random sampling is used to make the process reasonably fast even on very large tables. The number of values and histogram bins collected is now user-settable via an ALTER TABLE command. There is more still to do; the new stats are not being used everywhere they could be in the planner. But the remaining changes for this project should be localized, and the behavior is already better than before. A not-very-related change is that sorting now makes use of btree comparison routines if it can find one, rather than invoking '<' twice.
2001-04-18Make the world safe for passing whole rows of views to functions. ThisTom Lane
already worked fine for whole rows of tables, but not so well for views...
2001-03-27Repair pgindent damage to comments.Tom Lane
2001-03-22pgindent run. Make it all clean.Bruce Momjian
2001-03-08A subplan invoked within an aggregate function's argument shouldTom Lane
be allowed to receive ungrouped variables of the current query level. Curious that no one reported this bug before...
2001-02-16Take OUTER JOIN semantics into account when estimating the size of joinTom Lane
relations. It's not very bright, but at least it now knows that A LEFT JOIN B must produce at least as many rows as are in A ...
2001-02-12CleanupBruce Momjian
2001-02-12Add // -> /* */ mapping to pgindent.Bruce Momjian
2001-01-24Change Copyright from PostgreSQL, Inc to PostgreSQL Global Development Group.Bruce Momjian
2001-01-09Fix oversight in planning of GROUP queries: when an expression is usedTom Lane
as both a GROUP BY item and an output expression, the top-level Group node should just copy up the evaluated expression value from its input, rather than re-evaluating the expression. Aside from any performance benefit this might offer, this avoids a crash when there is a sub-SELECT in said expression.
2000-12-14Planner speedup hacking. Avoid saving useless pathkeys, so that pathTom Lane
comparison does not consider paths different when they differ only in uninteresting aspects of sort order. (We had a special case of this consideration for indexscans already, but generalize it to apply to ordered join paths too.) Be stricter about what is a canonical pathkey to allow faster pathkey comparison. Cache canonical pathkeys and dispersion stats for left and right sides of a RestrictInfo's clause, to avoid repeated computation. Total speedup will depend on number of tables in a query, but I see about 4x speedup of planning phase for a sample seven-table query.
2000-11-16Change SearchSysCache coding conventions so that a reference count isTom Lane
maintained for each cache entry. A cache entry will not be freed until the matching ReleaseSysCache call has been executed. This eliminates worries about cache entries getting dropped while still in use. See my posting to pg-hackers of even date for more info.
2000-11-12Restructure handling of inheritance queries so that they work with outerTom Lane
joins, and clean things up a good deal at the same time. Append plan node no longer hacks on rangetable at runtime --- instead, all child tables are given their own RT entries during planning. Concept of multiple target tables pushed up into execMain, replacing bug-prone implementation within nodeAppend. Planner now supports generating Append plans for inheritance sets either at the top of the plan (the old way) or at the bottom. Expanding at the bottom is appropriate for tables used as sources, since they may appear inside an outer join; but we must still expand at the top when the target of an UPDATE or DELETE is an inheritance set, because we actually need a different targetlist and junkfilter for each target table in that case. Fortunately a target table can't be inside an outer join... Bizarre mutual recursion between union_planner and prepunion.c is gone --- in fact, union_planner doesn't really have much to do with union queries anymore, so I renamed it grouping_planner.
2000-10-05Add proofreader's changes to docs.Bruce Momjian
Fix misspelling of disbursion to dispersion.
2000-10-05Reimplementation of UNION/INTERSECT/EXCEPT. INTERSECT/EXCEPT now meet theTom Lane
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!
2000-09-29Subselects in FROM clause, per ISO syntax: FROM (SELECT ...) [AS] alias.Tom Lane
(Don't forget that an alias is required.) Views reimplemented as expanding to subselect-in-FROM. Grouping, aggregates, DISTINCT in views actually work now (he says optimistically). No UNION support in subselects/views yet, but I have some ideas about that. Rule-related permissions checking moved out of rewriter and into executor. INITDB REQUIRED!
2000-09-25Use variable aliases, if supplied, rather than real column names inTom Lane
complaints about ungrouped variables. This is for consistency with behavior elsewhere, notably the fact that the relname is reported as an alias in these same complaints. Also, it'll work with subselect- in-FROM where old code didn't.
2000-09-12First cut at full support for OUTER JOINs. There are still a few looseTom Lane
ends to clean up (see my message of same date to pghackers), but mostly it works. INITDB REQUIRED!
2000-08-31Fix relative path references so that make knowns which dependencies referPeter Eisentraut
to one another. Sort out builddir vs srcdir variable namings. Remove some now obsoleted make variables.
2000-08-24SQL-language functions are now callable in ordinary fmgr contexts ...Tom Lane
for example, an SQL function can be used in a functional index. (I make no promises about speed, but it'll work ;-).) Clean up and simplify handling of functions returning sets.
2000-08-21fmgr interface mopup work. Use new DatumGetBool and BoolGetDatumTom Lane
macros where appropriate (the code used to have several different ways of doing that, including Int32, Int8, UInt8, ...). Remove last few references to float32 and float64 typedefs --- it's all float4/float8 now. The typedefs themselves should probably stay in c.h for a release or two, though, to avoid breaking user-written C functions.
2000-08-13Clean up handling of variable-free qual clauses. System now does theTom Lane
right thing with variable-free clauses that contain noncachable functions, such as 'WHERE random() < 0.5' --- these are evaluated once per potential output tuple. Expressions that contain only Params are now candidates to be indexscan quals --- for example, 'var = ($1 + 1)' can now be indexed. Cope with RelabelType nodes atop potential indexscan variables --- this oversight prevents 7.0.* from recognizing some potentially indexscanable situations.
2000-08-08Remove 'func_tlist' from Func expression nodes, likewise 'param_tlist'Tom Lane
from Param nodes, per discussion a few days ago on pghackers. Add new expression node type FieldSelect that implements the functionality where it's actually needed. Clean up some other unused fields in Func nodes as well. NOTE: initdb forced due to change in stored expression trees for rules.
2000-07-27Make planner safe for recursive calls --- needed for cases whereTom Lane
eval_const_expressions tries to simplify an SQL function.
2000-07-12First stage of reclaiming memory in executor by resetting short-termTom Lane
memory contexts. Currently, only leaks in expressions executed as quals or projections are handled. Clean up some old dead cruft in executor while at it --- unused fields in state nodes, that sort of thing.
2000-07-05Update textin() and textout() to new fmgr style. This is just phaseTom Lane
one of updating the whole text datatype, but there are so dang many calls of these two routines that it seems worth a separate commit.
2000-06-20Make inheritance planning logic a little simpler and clearer,Tom Lane
hopefully even a little faster.
2000-06-18Reimplement nodeMaterial to use a temporary BufFile (or even memory, if theTom Lane
materialized tupleset is small enough) instead of a temporary relation. This was something I was thinking of doing anyway for performance, and Jan says he needs it for TOAST because he doesn't want to cope with toasting noname relations. With this change, the 'noname table' support in heap.c is dead code, and I have accordingly removed it. Also clean up 'noname' plan handling in planner --- nonames are either sort or materialize plans, and it seems less confusing to handle them separately under those names.
2000-06-17Fix performance problems with pg_index lookups (see, for example,Tom Lane
discussion of 5/19/00). pg_index is now searched for indexes of a relation using an indexscan. Moreover, this is done once and cached in the relcache entry for the relation, in the form of a list of OIDs for the indexes. This list is used by the parser and executor to drive lookups in the pg_index syscache when they want to know the properties of the indexes. Net result: index information will be fully cached for repetitive operations such as inserts.
2000-06-15Clean up #include's.Bruce Momjian
2000-06-09Cause inheritance patch to meet minimum coding standards (no gccTom Lane
warnings).
2000-06-09Inheritance overhaul by Chris Bitmead <chris@bitmead.com>Bruce Momjian
2000-06-08Mark functions as static and ifdef NOT_USED as appropriate.Bruce Momjian
2000-05-30Third round of fmgr updates: eliminate calls using fmgr() andTom Lane
fmgr_faddr() in favor of new-style calls. Lots of cleanup of sloppy casts to use XXXGetDatum and DatumGetXXX ...
2000-05-30Remove unused include files. Do not touch /port or includes used by defines.Bruce Momjian