Notiziario settimanale PostgreSQL – 19 aprile 2009

(Traduzione parziale in lingua italiana delle PostgreSQL Weekly News a cura di Gianni Ciolli gianni.ciolli@2ndquadrant.it)

Rilasciata la versione 8.4 beta 1. Partecipate al test! http://www.postgresql.org/developer/beta

È disponibile il video "PostgreSQL in the Cloud". Grazie a Christophe Pettus per le riprese e a Dirk Jagdmann per aver realizzato lo streaming live durante l’evento. http://media.postgresql.org/sfpug/sfpug-cloud-20090408.mov http://www.vimeo.com/4144396

Novità sul prodotto PostgreSQL

Rilasciata la versione 3.1.1 di Archiveopteryx, un gestore di email basato su PostgreSQL. http://www.archiveopteryx.org/3.1.1

Rilasciata la versione 2.7 di Benetl 2.7, un tool ETL per files che usa PostgreSQL. http://www.benetl.net

Rilasciata la versione 2.13.0 di DBD::Pg, un connettore Perl per PostgreSQL. http://search.cpan.org/dist/DBD-Pg/

La novità della settimana di PostgreSQL 8.4

Autotuning FSM: Ti piacevano i parametri GUC max_fsm_relations e max_fsm_pages? Beh, peccato, non ci sono più. Grazie a Heikki Linnakangas adesso quei parametri si regolano da soli.

Il suggerimento della settimana

PostgreSQL supporta lo standard SQL INFORMATION_SCHEMA, che contiene informazioni su tabelle, colonne, vincoli e viste in un formato tabellare standard che è lo stesso usato da Oracle, DB2 e MySQL. Lo trovate nello schema predefinito information_schema.

Offerte di lavoro su PostgreSQL per aprile 2009

http://archives.postgresql.org/pgsql-jobs/2009-04/threads.php

Notizie locali su PostgreSQL

Il PgDay di Florianopolis (Brasile) sarà il 22 maggio. Mettetevi in contatto con Dickson S. Guedes (guedes AT guedesoft DOT net) per partecipare o inviare un lavoro. http://www.postgresql.org.br/eventos/pgday/sc

La Percona Performance Conference si svolgerà presso il Santa Clara Convention Center, Santa Clara, California, USA http://conferences.percona.com/

Aperto il CfP per il PgDay São Paulo, che si terrà il 24 aprile. Per partecipare mettersi in contatto con marins DOT consultoria AT gmail DOT com oppure marcelojscosta AT gmail DOT com.

La PostgreSQL Conference U. S. (JDCon) organizzerà un PgDay nell’ambito della LinuxFest Northwest (25, 26 aprile). Informazioni su come proporre una comunicazione sono disponibili sul sito http://www.postgresqlconference.org/

Ci saranno anche dei PgDay il 29 aprile a Porto Velho, RO, e il 30 in Ji-Parana, RO. Per partecipare mettersi in contatto con Luis Fernando Bueno: proflfbueno AT gmail DOT com.

Michael Renner farà un workshop sulla replica con PostgreSQL a Netways OSDC 2009 il 29 e 30 aprile a Norimberga, in Germania. http://www.netways.de/english/osdc/y2009/programm/w/michael_renner_postgresql_repliziert_ein_ueberblick/

Nei giorni 21 e 22 maggio 2009 all’università di Ottawa, in Canada, si terrà PGCon 2009. Nei due giorni precedenti si terranno dei tutorials. http://www.pgcon.org/2009/

Segnatevi la data: pgDay San Jose (USA). Domenica 19 luglio subito prima di OSCON. Saranno presto annunciate ulteriori informazioni! (incluso il call for papers)

Il 23 e 24 ottobre 2009 si svolgerà PGCon Brazil, presso Unicamp, nella città di Campinas, stato di San Paolo.

Rassegna stampa su PostgreSQL

Planet PostgreSQL: http://planet.postgresql.org/

Questo notiziario settimanale PostgreSQL è stato realizzato da David Fetter e Josh Berkus; traduzione parziale in lingua italiana a cura di Gianni Ciolli.

Notizie o annunci destinati a questo notiziario dovranno pervenire entro la mezzanotte di domenica (le 15 nel fuso orario della California). I comunicati in lingua italiana dovranno essere inviati a pwn@itpug.org; per le lingue inglese o tedesca, si scriva rispettivamente a david@fetter.org o a pwd@pgug.de.

Patch applicate

Tom Lane committed:

• In pgsql/doc/src/sgml/release.sgml, make a copy-editing pass over the 8.4 release notes.

• In pgsql/doc/src/sgml/textsearch.sgml, do some copy-editing on description of ts_headline().

• In pgsql/src/backend/parser/scan.l, fix broken {xufailed} production that made HEAD fail on select u&42 from table-with-a-u-column; Also fix missing SET_YYLLOC() in the {dolqfailed} production that I suppose this was based on. The latter is a pre-existing bug, but the only effect is to misplace the error cursor by one token, so probably not worth backpatching.

• Fix planner to restore its previous level of intelligence about pushing constants through full joins, as in SELECT 2ndquadrant_italia_mod.txt 2ndquadrant_italia.txt da_installare_pandoc hdoisajds.sh risultati step2 FROM tenk1 a FULL JOIN tenk1 b USING (unique1) WHERE unique1 = 42; which should generate a fairly cheap plan where we apply the constraint unique1 = 42 in each relation scan. This had been broken by my patch of 2008-06-27, which is now reverted in favor of a more invasive but hopefully less incorrect approach. That patch was meant to prevent incorrect extraction of OR’d indexclauses from OR conditions above an outer join. To do that correctly we need more information than the outerjoin_delay flag can provide, so add a nullable_relids field to RestrictInfo that records exactly which relations are nulled by outer joins that are underneath a particular qual clause. A side benefit is that we can make the test in create_or_index_quals more specific: it is now smart enough to extract an OR’d indexclause into the outer side of an outer join, even though it must not do so in the inner side. The old coding couldn’t distinguish these cases so it could not do either.

• In pgsql/src/backend/optimizer/path/costsize.c, bump disable_cost up from 1e8 to 1e10, per gripe from Kris Jurka.

• Revise plpgsql’s scanner to process comments and string literals in a way more nearly matching the core SQL scanner. The user-visible effects are: 1. Block comments (slash-star comments) now nest, as per SQL spec. 2. In standard_conforming_strings mode, backslash as the last character of a non-E string literal is now correctly taken as an ordinary character; formerly it was misinterpreted as escaping the ending quote. (Since the string also had to pass through the core scanner, this invariably led to syntax errors.) 3. Formerly, backslashes in the format string of RAISE were always treated as quoting the next character, regardless of mode. Now, they are ordinary characters with standard_conforming_strings on, while with it off, they introduce the same set of escapes as in the core SQL scanner. Also, escape_string_warning is now effective for RAISE format strings. These changes make RAISE format strings work just like any other string literal. This is implemented by copying and pasting a lot of logic from the core scanner. It would be a good idea to look into getting rid of plpgsql’s scanner entirely in favor of using the core scanner. However, that involves more change than I can justify making during beta — in particular, the core scanner would have to become re-entrant. In passing, remove the kluge that made the plpgsql scanner emit T_FUNCTION or T_TRIGGER as a made-up first token. That presumably had some value once upon a time, but now it’s just useless complication for both the scanner and the grammar.

• Fix estimate_num_groups() to not fail on PlaceHolderVars, per report from Stefan Kaltenbrunner. The most reasonable behavior (at least for the near term) seems to be to ignore the PlaceHolderVar and examine its argument instead. In support of this, change the API of pull_var_clause() to allow callers to request recursion into PlaceHolderVars. Currently estimate_num_groups() is the only customer for that behavior, but where there’s one there may be others.

• In pgsql/doc/src/sgml/textsearch.sgml, fix textsearch documentation examples to not recommend concatenating separate fields without putting a space between. Per gripe from Rick Schumeyer.

• Fix de-escaping checks so that we will reject 000 as well as other invalidly encoded sequences. Per discussion of a couple of days ago.

• Rethink the idea of having plpgsql depend on parser/gram.h. Aside from the fact that this is breaking the MSVC build, it’s probably not really a good idea to expand the dependencies of gram.h any further than the core parser; for instance the value of SCONST might depend on which bison version you’d built with. Better to expose an additional call point in parser.c, so move what I had put into pl_funcs.c into parser.c. Also PGDLLIMPORT’ify the reference to standard_conforming_strings, per buildfarm results.

• Assorted portability fixes for Borland C, from Pavel Golub.

Alvaro Herrera committed:

• In pgsql/src/bin/pg_dump/pg_restore.c, make new strings more alike previously existing messages.

• In pgsql/src/bin/pg_dump/pg_restore.c, pg_restore -jN does not equate "multiple jobs", so partly revert the previous patch. Per note from Tom Lane.

• In pgsql/src/backend/commands/dbcommands.c, add missing periods.

• In pgsql/src/backend/libpq/hba.c, add missing gettext calls around some strings. Also remove quotes around the %s that they expand to, per comment from Tom Lane.

• In pgsql/src/backend/utils/adt/arrayfuncs.c, substitute extraneous underscores with spaces.

• In pgsql/src/test/regress/expected/arrays.out, fix the regression test error message for array_fill, too. Per note from Andrew Dunstan.

Bruce Momjian committed:

• In pgsql/src/interfaces/libpq/fe-secure.c, add libpq error message text on how to handle missing root.crt file.

• In pgsql/doc/src/sgml/libpq.sgml, reformat ‘sslmode’ options into an SGML table; improve wording.

• In pgsql/doc/src/sgml/libpq.sgml, fix SGML markup I broke yesterday.

• Remove mention of pre-7.1 inheritance behavior from /ref pages; keep mentions in main documentation.

• In pgsql/doc/src/sgml/release.sgml, add Ron Mayer as primary contributor for, "support the IS0 8601 interval syntax" based on private email from Ron.

Magnus Hagander committed:

• In pgsql/contrib/pgcrypto/crypt-md5.c, remove beer-ware license from crypt-md5.c, per approval from Poul-Henning Kamp. This makes the file the same standard 2-clause BSD as the rest of PostgreSQL.

Patch rifiutate (per adesso)

KaiGai Kohei’s patch to separate the ACL for SELECT … FOR UPDATE from UPDATE. Not needed.

Patch in coda

Abhijit Menon-Sen sent in another revision of his patch to test quoting in PL/pgSQL.

ITAGAKI Takahiro sent in a patch to implement GetPlatformEncoding() and convert absolute file paths from database encoding to platform encoding.

David Fetter sent in three patches to make df describe whether a function is normal, aggregate, trigger or windowing and let people choose any or all of those to see.

ITAGAKI Takahiro sent in a WIP patch to solve server-side encoding issues.

Fujii Masao sent in another revision of his trigger patch for pg_standby.

Marko Kreen sent in a patch to add u and U as unicode escapes.

KaiGai Kohei sent in another revision of his SE-PostgreSQL patches.