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2023-01-02Update copyright for 2023Bruce Momjian
Backpatch-through: 11
2022-01-08Update copyright for 2022Bruce Momjian
Backpatch-through: 10
2021-01-02Update copyright for 2021Bruce Momjian
Backpatch-through: 9.5
2020-09-17Remove support for postfix (right-unary) operators.Tom Lane
This feature has been a thorn in our sides for a long time, causing many grammatical ambiguity problems. It doesn't seem worth the pain to continue to support it, so remove it. There are some follow-on improvements we can make in the grammar, but this commit only removes the bare minimum number of productions, plus assorted backend support code. Note that pg_dump and psql continue to have full support, since they may be used against older servers. However, pg_dump warns about postfix operators. There is also a check in pg_upgrade. Documentation-wise, I (tgl) largely removed the "left unary" terminology in favor of saying "prefix operator", which is a more standard and IMO less confusing term. I included a catversion bump, although no initial catalog data changes here, to mark the boundary at which oprkind = 'r' stopped being valid in pg_operator. Mark Dilger, based on work by myself and Robert Haas; review by John Naylor Discussion: https://postgr.es/m/[email protected]
2020-01-01Update copyrights for 2020Bruce Momjian
Backpatch-through: update all files in master, backpatch legal files through 9.4
2019-01-02Update copyright for 2019Bruce Momjian
Backpatch-through: certain files through 9.4
2018-01-03Update copyright for 2018Bruce Momjian
Backpatch-through: certain files through 9.3
2017-09-13Distinguish selectivity of < from <= and > from >=.Tom Lane
Historically, the selectivity functions have simply not distinguished < from <=, or > from >=, arguing that the fraction of the population that satisfies the "=" aspect can be considered to be vanishingly small, if the comparison value isn't any of the most-common-values for the variable. (If it is, the code path that executes the operator against each MCV will take care of things properly.) But that isn't really true unless we're dealing with a continuum of variable values, and in practice we seldom are. If "x = const" would estimate a nonzero number of rows for a given const value, then it follows that we ought to estimate different numbers of rows for "x < const" and "x <= const", even if the const is not one of the MCVs. Handling this more honestly makes a significant difference in edge cases, such as the estimate for a tight range (x BETWEEN y AND z where y and z are close together). Hence, split scalarltsel into scalarltsel/scalarlesel, and similarly split scalargtsel into scalargtsel/scalargesel. Adjust <= and >= operator definitions to reference the new selectivity functions. Improve the core ineq_histogram_selectivity() function to make a correction for equality. (Along the way, I learned quite a bit about exactly why that function gives good answers, which I tried to memorialize in improved comments.) The corresponding join selectivity functions were, and remain, just stubs. But I chose to split them similarly, to avoid confusion and to prevent the need for doing this exercise again if someone ever makes them less stubby. In passing, change ineq_histogram_selectivity's clamp for extreme probability estimates so that it varies depending on the histogram size, instead of being hardwired at 0.0001. With the default histogram size of 100 entries, you still get the old clamp value, but bigger histograms should allow us to put more faith in edge values. Tom Lane, reviewed by Aleksander Alekseev and Kuntal Ghosh Discussion: https://postgr.es/m/[email protected]
2017-01-03Update copyright via script for 2017Bruce Momjian
2016-01-02Update copyright for 2016Bruce Momjian
Backpatch certain files through 9.1
2015-01-06Update copyright for 2015Bruce Momjian
Backpatch certain files through 9.0
2014-01-07Update copyright for 2014Bruce Momjian
Update all files in head, and files COPYRIGHT and legal.sgml in all back branches.
2013-01-01Update copyrights for 2013Bruce Momjian
Fully update git head, and update back branches in ./COPYRIGHT and legal.sgml files.
2012-01-01Update copyright notices for year 2012.Bruce Momjian
2011-01-01Stamp copyrights for year 2011.Bruce Momjian
2010-11-23Remove useless whitespace at end of linesPeter Eisentraut
2010-09-20Remove cvs keywords from all files.Magnus Hagander
2010-01-02Update copyright for the year 2010.Bruce Momjian
2009-01-01Update copyright for 2009.Bruce Momjian
2008-01-01Update copyrights in source tree to 2008.Bruce Momjian
2007-01-05Update CVS HEAD for 2007 copyright. Back branches are typically notBruce Momjian
back-stamped for this.
2006-03-05Update copyright for 2006. Update scripts.Bruce Momjian
2004-12-31Tag appropriate files for rc3PostgreSQL Daemon
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 ...
2004-08-29Update copyright to 2004.Bruce Momjian
2003-11-29$Header: -> $PostgreSQL Changes ...PostgreSQL Daemon
2003-10-21Update the complex-datatype example to V1 function calling conventions,Tom Lane
and add binary send/receive functions. Fix some other grottiness such as failure to mark the C functions STRICT.
2003-08-04Fix some copyright notices that weren't updated. Improve copyright toolTom Lane
so it won't miss 'em again.
2002-08-22Add a bunch of pseudo-types to replace the behavior formerly associatedTom Lane
with OPAQUE, as per recent pghackers discussion. I still want to do some more work on the 'cstring' pseudo-type, but I'm going to commit the bulk of the changes now before the tree starts shifting under me ...
2002-07-30Rewrite xindex.sgml for CREATE OPERATOR CLASS. catalogs.sgml finallyTom Lane
contains descriptions of every single system table. Update 'complex' tutorial example too.
2002-04-17Opclasses live in namespaces. I also took the opportunity to createTom Lane
an 'opclass owner' column in pg_opclass. Nothing is done with it at present, but since there are plans to invent a CREATE OPERATOR CLASS command soon, we'll probably want DROP OPERATOR CLASS too, which suggests that a notion of ownership would be a good idea.
2001-10-26Remove no-longer-needed dependencies on DLSUFFIX.Tom Lane
2001-10-03DROP AGGREGATE and COMMENT ON AGGREGATE now accept the expected syntaxTom Lane
'aggname (aggtype)'. The old syntax 'aggname aggtype' is still accepted for backwards compatibility. Fix pg_dump, which was actually broken for most cases of user-defined aggregates. Clean up error messages associated with these commands.
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.
2000-07-17Revise aggregate functions per earlier discussions in pghackers.Tom Lane
There's now only one transition value and transition function. NULL handling in aggregates is a lot cleaner. Also, use Numeric accumulators instead of integer accumulators for sum/avg on integer datatypes --- this avoids overflow at the cost of being a little slower. Implement VARIANCE() and STDDEV() aggregates in the standard backend. Also, enable new LIKE selectivity estimators by default. Unrelated change, but as long as I had to force initdb anyway...
2000-03-28Fix some bogosity in the tutorial examples.Tom Lane
2000-01-24First cut at making useful selectivity estimates for range queriesTom Lane
(ie, WHERE x > lowbound AND x < highbound). It's not very bright yet but it does something useful. Also, rename intltsel/intgtsel to scalarltsel/scalargtsel to reflect usage better. Extend convert_to_scalar to do something a little bit useful with string data types. Still need to make it do something with date/time datatypes, but I'll wait for Thomas's datetime unification dust to settle first. Eventually the routine ought not have any type-specific knowledge at all; it ought to be calling a type-dependent routine found via a pg_type column; but that's a task for another day.
2000-01-22Revise handling of index-type-specific indexscan cost estimation, perTom Lane
pghackers discussion of 5-Jan-2000. The amopselect and amopnpages estimators are gone, and in their place is a per-AM amcostestimate procedure (linked to from pg_am, not pg_amop).
1998-03-01From: Darren King <[email protected]>Marc G. Fournier
1. Make 'all' works without complaint. Don't have to add the .exp files to the files list. They are made automagically when making the respective shared lib file. Only port that actually uses EXPSUFF (from makefiles/Makefile.*) is Aix, so if this breaks anybody else, let me know, asap. 2. Make 'clean' actually cleans up correctly. Previously, it would leave the .o files in C-code directory. 3. Changed references to reflect new location of .c files. 4. Added DELETE statements to complex.source so that it tidies up when done. Previously, it would leave things in pg_amop, pg_amproc and pg_opclass. Only possible to do this with the new SUBSELECT code in 6.3. Nice work, fellas... Not deleting the index entries would cause a non-fatal error if complex.sql was run again on the same database. Much tidier now. 5. Corrected the README. obj directory hasn't existed since Bryan redid the make way back when. Also changed the snipet from psql to match the current version. POSTGRES95?!? I don't think so. :)
1998-02-28From: Darren King <[email protected]>Marc G. Fournier
Seem to remember someone posting to one of the lists a while back that the tutorial code wouldn't compile and/or run. Found four problems with it that will let it run. 1. Tutorial makefile had a recursive use of DLOBJS. 2. Some tutorial needed semi-colons added to many statements. 3. Complex tutorial didn't clean up after itself. 4. Advanced had a time-travel example. Commented it out and put a line pointing the user to contrib/spi/README.
1996-12-28Here is a bug fix and some spelling changes for the complex number tutorialBruce Momjian
code. I have also written a complete complex number package based on this tutorial; I will submit this as a contribution soon. Is there a particular format for contributed tar files? I have a C source file, two SQL files, and a Makefile. Thomas Lockhart
1996-07-09Postgres95 1.01 Distribution - Virgin SourcesPG95-1_01Marc G. Fournier