summaryrefslogtreecommitdiff
path: root/src/backend/commands
AgeCommit message (Collapse)Author
2007-08-01Support an optional asynchronous commit mode, in which we don't flush WALTom Lane
before reporting a transaction committed. Data consistency is still guaranteed (unlike setting fsync = off), but a crash may lose the effects of the last few transactions. Patch by Simon, some editorialization by Tom.
2007-07-17Fix incorrect optimization of foreign-key checks. When an UPDATE on theTom Lane
referencing table does not change the tuple's FK column(s), we don't bother to check the PK table since the constraint was presumably already valid. However, the check is still necessary if the tuple was inserted by our own transaction, since in that case the INSERT trigger will conclude it need not make the check (since its version of the tuple has been deleted). We got this right for simple cases, but not when the insert and update are in different subtransactions of the current top-level transaction; in such cases the FK check would never be made at all. (Hence, problem dates back to 8.0 when subtransactions were added --- it's actually the subtransaction version of a bug fixed in 7.3.5.) Fix, and add regression test cases. Report and fix by Affan Salman.
2007-07-17Implement CREATE TABLE LIKE ... INCLUDING INDEXES. Patch from NikhilS,Neil Conway
based in part on an earlier patch from Trevor Hardcastle, and reviewed by myself.
2007-07-03Add ALTER VIEW ... RENAME TO, and a RENAME TO clause to ALTER SEQUENCE.Neil Conway
Sequences and views could previously be renamed using ALTER TABLE, but this was a repeated source of confusion for users. Update the docs, and psql tab completion. Patch from David Fetter; various minor fixes by myself.
2007-07-01Avoid memory leakage when a series of subtransactions invoke AFTER triggersTom Lane
that are fired at end-of-statement (as is the normal case for foreign keys, for example). In this situation the per-subxact deferred trigger context is always empty when subtransaction exit is reached; so we could free it, but were not doing so, leading to an intratransaction leak of 8K or more per subtransaction. Per off-list example from Viatcheslav Kalinin subsequent to bug #3418 (his original bug report omitted a foreign key constraint needed to cause this leak). Back-patch to 8.2; prior versions were not using per-subxact contexts for deferred triggers, so did not have this leak.
2007-06-28Implement "distributed" checkpoints in which the checkpoint I/O is spreadTom Lane
over a fairly long period of time, rather than being spat out in a burst. This happens only for background checkpoints carried out by the bgwriter; other cases, such as a shutdown checkpoint, are still done at full speed. Remove the "all buffers" scan in the bgwriter, and associated stats infrastructure, since this seems no longer very useful when the checkpoint itself is properly throttled. Original patch by Itagaki Takahiro, reworked by Heikki Linnakangas, and some minor API editorialization by me.
2007-06-23Separate parse-analysis for utility commands out of parser/analyze.cTom Lane
(which now deals only in optimizable statements), and put that code into a new file parser/parse_utilcmd.c. This helps clarify and enforce the design rule that utility statements shouldn't be processed during the regular parse analysis phase; all interpretation of their meaning should happen after they are given to ProcessUtility to execute. (We need this because we don't retain any locks for a utility statement that's in a plan cache, nor have any way to detect that it's stale.) We are also able to simplify the API for parse_analyze() and related routines, because they will now always return exactly one Query structure. In passing, fix bug #3403 concerning trying to add a serial column to an existing temp table (this is largely Heikki's work, but we needed all that restructuring to make it safe).
2007-06-20CREATE DOMAIN ... DEFAULT NULL failed because gram.y special-cases DEFAULTTom Lane
NULL and DefineDomain didn't. Bug goes all the way back to original coding of domains. Per bug #3396 from Sergey Burladyan.
2007-06-20Minor code cleanup: calling FreeFile() before ereport(ERROR) is notNeil Conway
necessary, since files opened via AllocateFile() are closed automatically as part of error recovery.
2007-06-17Marginal hacking to improve the speed of COPY OUT. I had found in a bit ofTom Lane
profiling that CopyAttributeOutText was taking an unreasonable fraction of the backend run time (like 66%!) on the following trivial test case: $ time psql -c "copy (select repeat('xyzzy',50) from generate_series(1,10000000)) to stdout" regression >/dev/null The time is all being spent on scanning the string for characters to be escaped, which most of the time there aren't any of. Some tweaking to take as many tests as possible out of the inner loop reduced the runtime of this example by more than 10%. In a real-world case it wouldn't be as useful a speedup, but it still seems worth adding a few lines here.
2007-06-15Tweak the API for per-datatype typmodin functions so that they are passedTom Lane
an array of strings rather than an array of integers, and allow any simple constant or identifier to be used in typmods; for example create table foo (f1 widget(42,'23skidoo',point)); Of course the typmodin function has still got to pack this info into a non-negative int32 for storage, but it's still a useful improvement in flexibility, especially considering that you can do nearly anything if you are willing to keep the info in a side table. We can get away with this change since we have not yet released a version providing user-definable typmods. Per discussion.
2007-06-14Avoid having autovacuum run multiple ANALYZE commands in a single transaction,Alvaro Herrera
to prevent possible deadlock problems. Per request from Tom Lane.
2007-06-07Rework temp_tablespaces patch so that temp tablespaces are assigned separatelyTom Lane
for each temp file, rather than once per sort or hashjoin; this allows spreading the data of a large sort or join across multiple tablespaces. (I remain dubious that this will make any difference in practice, but certain people insisted.) Arrange to cache the results of parsing the GUC variable instead of recomputing from scratch on every demand, and push usage of the cache down to the bottommost fd.c level.
2007-06-03Clarify some error messages about duplicate things.Peter Eisentraut
2007-06-03Create a GUC parameter temp_tablespaces that allows selection of theTom Lane
tablespace(s) in which to store temp tables and temporary files. This is a list to allow spreading the load across multiple tablespaces (a random list element is chosen each time a temp object is to be created). Temp files are not stored in per-database pgsql_tmp/ directories anymore, but per-tablespace directories. Jaime Casanova and Albert Cervera, with review by Bernd Helmle and Tom Lane.
2007-06-02Minimal message corrections found by spell checker.Peter Eisentraut
2007-06-01Make CREATE/DROP/RENAME DATABASE wait a little bit to see if other backendsTom Lane
will exit before failing because of conflicting DB usage. Per discussion, this seems a good idea to help mask the fact that backend exit takes nonzero time. Remove a couple of thereby-obsoleted sleeps in contrib and PL regression test sequences.
2007-05-31Make some messages more consistentPeter Eisentraut
2007-05-30Make large sequential scans and VACUUMs work in a limited-size "ring" ofTom Lane
buffers, rather than blowing out the whole shared-buffer arena. Aside from avoiding cache spoliation, this fixes the problem that VACUUM formerly tended to cause a WAL flush for every page it modified, because we had it hacked to use only a single buffer. Those flushes will now occur only once per ring-ful. The exact ring size, and the threshold for seqscans to switch into the ring usage pattern, remain under debate; but the infrastructure seems done. The key bit of infrastructure is a new optional BufferAccessStrategy object that can be passed to ReadBuffer operations; this replaces the former StrategyHintVacuum API. This patch also changes the buffer usage-count methodology a bit: we now advance usage_count when first pinning a buffer, rather than when last unpinning it. To preserve the behavior that a buffer's lifetime starts to decrease when it's released, the clock sweep code is modified to not decrement usage_count of pinned buffers. Work not done in this commit: teach GiST and GIN indexes to use the vacuum BufferAccessStrategy for vacuum-driven fetches. Original patch by Simon, reworked by Heikki and again by Tom.
2007-05-25Create hooks to let a loadable plugin monitor (or even replace) the plannerTom Lane
and/or create plans for hypothetical situations; in particular, investigate plans that would be generated using hypothetical indexes. This is a heavily-rewritten version of the hooks proposed by Gurjeet Singh for his Index Advisor project. In this formulation, the index advisor can be entirely a loadable module instead of requiring a significant part to be in the core backend, and plans can be generated for hypothetical indexes without requiring the creation and rolling-back of system catalog entries. The index advisor patch as-submitted is not compatible with these hooks, but it needs significant work anyway due to other 8.2-to-8.3 planner changes. With these hooks in the core backend, development of the advisor can proceed as a pgfoundry project.
2007-05-19Fix dumb compile error in the last patch.Alvaro Herrera
2007-05-18Have CLUSTER advance the table's relfrozenxid. The new frozen point is theAlvaro Herrera
FreezeXid introduced in a recent commit, so there isn't any data loss in this approach. Doing it causes ALTER TABLE (or rather, the forms of it that cause a full table rewrite) to be affected as well. In this case, the frozen point is RecentXmin, because after the rewrite all the tuples are relabeled with the rewriting transaction's Xid. TOAST tables are fixed automatically as well, as fallout of the way they were already being handled in the respective code paths. With this patch, there is no longer need to VACUUM tables for Xid wraparound purposes that have been cleaned up via TRUNCATE or CLUSTER.
2007-05-17Move the tuple freezing point in CLUSTER to a point further back in the past,Alvaro Herrera
to avoid losing useful Xid information in not-so-old tuples. This makes CLUSTER behave the same as VACUUM as far a tuple-freezing behavior goes (though CLUSTER does not yet advance the table's relfrozenxid). While at it, move the actual freezing operation in rewriteheap.c to a more appropriate place, and document it thoroughly. This part of the patch from Tom Lane.
2007-05-16Have TRUNCATE advance the affected table's relfrozenxid to RecentXmin, toAlvaro Herrera
avoid a later needless VACUUM for Xid-wraparound purposes. We can do this since the table is known to be left empty, so no Xid remains on it. Per discussion.
2007-05-14Get rid of the pg_shdepend entry for a TOAST table; it's unnecessary sinceTom Lane
there's an indirect dependency on the owner via the parent table. We were already handling indexes that way, but not toast tables for some reason. Saves a little catalog space and cuts down the verbosity of checkSharedDependencies reports.
2007-05-12Fix the problem that creating a user-defined type named _foo, followed by oneTom Lane
named foo, would work but the other ordering would not. If a user-specified type or table name collides with an existing auto-generated array name, just rename the array type out of the way by prepending more underscores. This should not create any backward-compatibility issues, since the cases in which this will happen would have failed outright in prior releases. Also fix an oversight in the arrays-of-composites patch: ALTER TABLE RENAME renamed the table's rowtype but not its array type.
2007-05-11Fix my oversight in enabling domains-of-domains: ALTER DOMAIN ADD CONSTRAINTTom Lane
needs to check the new constraint against columns of derived domains too. Also, make it error out if the domain to be modified is used within any composite-type columns. Eventually we should support that case, but it seems a bit painful, and not suitable for a back-patch. For the moment just let the user know we can't do it. Backpatch to 8.2, which is the only released version that allows nested domains. Possibly the other part should be back-patched further.
2007-05-11Support arrays of composite types, including the rowtypes of regular tablesTom Lane
and views (but not system catalogs, nor sequences or toast tables). Get rid of the hardwired convention that a type's array type is named exactly "_type", instead using a new column pg_type.typarray to provide the linkage. (It still will be named "_type", though, except in odd corner cases such as maximum-length type names.) Along the way, make tracking of owner and schema dependencies for types more uniform: a type directly created by the user has these dependencies, while a table rowtype or auto-generated array type does not have them, but depends on its parent object instead. David Fetter, Andrew Dunstan, Tom Lane
2007-05-04Add a line to the EXPLAIN ANALYZE output for a Sort node, showing theTom Lane
actual sort strategy and amount of space used. By popular demand.
2007-05-02Fix things so that when CREATE INDEX CONCURRENTLY sets pg_index.indisvalidTom Lane
true at the very end of its processing, the update is broadcast via a shared-cache-inval message for the index; without this, existing backends that already have relcache entries for the index might never see it become valid. Also, force a relcache inval on the index's parent table at the same time, so that any cached plans for that table are re-planned; this ensures that the newly valid index will be used if appropriate. Aside from making C.I.C. behave more reasonably, this is necessary infrastructure for some aspects of the HOT patch. Pavan Deolasee, with a little further stuff from me.
2007-04-30Implement rate-limiting logic on how often backends will attempt to sendTom Lane
messages to the stats collector. This avoids the problem that enabling stats_row_level for autovacuum has a significant overhead for short read-only transactions, as noted by Arjen van der Meijden. We can avoid an extra gettimeofday call by piggybacking on the one done for WAL-logging xact commit or abort (although that doesn't help read-only transactions, since they don't WAL-log anything). In my proposal for this, I noted that we could change the WAL log entries for commit/abort to record full TimestampTz precision, instead of only time_t as at present. That's not done in this patch, but will be committed separately.
2007-04-27Modify processing of DECLARE CURSOR and EXPLAIN so that they can resolve theTom Lane
types of unspecified parameters when submitted via extended query protocol. This worked in 8.2 but I had broken it during plancache changes. DECLARE CURSOR is now treated almost exactly like a plain SELECT through parse analysis, rewrite, and planning; only just before sending to the executor do we divert it away to ProcessUtility. This requires a special-case check in a number of places, but practically all of them were already special-casing SELECT INTO, so it's not too ugly. (Maybe it would be a good idea to merge the two by treating IntoClause as a form of utility statement? Not going to worry about that now, though.) That approach doesn't work for EXPLAIN, however, so for that I punted and used a klugy solution of running parse analysis an extra time if under extended query protocol.
2007-04-26Fix dynahash.c to suppress hash bucket splits while a hash_seq_search() scanTom Lane
is in progress on the same hashtable. This seems the least invasive way to fix the recently-recognized problem that a split could cause the scan to visit entries twice or (with much lower probability) miss them entirely. The only field-reported problem caused by this is the "failed to re-find shared lock object" PANIC in COMMIT PREPARED reported by Michel Dorochevsky, which was caused by multiply visited entries. However, it seems certain that mdsync() is vulnerable to missing required fsync's due to missed entries, and I am fearful that RelationCacheInitializePhase2() might be at risk as well. Because of that and the generalized hazard presented by this bug, back-patch all the supported branches. Along the way, fix pg_prepared_statement() and pg_cursor() to not assume that the hashtables they are examining will stay static between calls. This is risky regardless of the newly noted dynahash problem, because hash_seq_search() has never promised to cope with deletion of table entries other than the just-returned one. There may be no bug here because the only supported way to call these functions is via ExecMakeTableFunctionResult() which will cycle them to completion before doing anything very interesting, but it seems best to get rid of the assumption. This affects 8.2 and HEAD only, since those functions weren't there earlier.
2007-04-26Rename the newly-added commands for discarding session state.Neil Conway
RESET SESSION, RESET PLANS, and RESET TEMP are now DISCARD ALL, DISCARD PLANS, and DISCARD TEMP, respectively. This is to avoid confusion with the pre-existing RESET variants: the DISCARD commands are not actually similar to RESET. Patch from Marko Kreen, with some minor editorialization.
2007-04-19Silence compiler warnings, per Bruce.Alvaro Herrera
2007-04-18Enable configurable log of autovacuum actions. Initial patch from SimonAlvaro Herrera
Riggs, additional code and docs by me. Per discussion.
2007-04-18Update docs/error message for CSV quote/escape --- must be ASCII.Bruce Momjian
Backpatch doc change to 8.2.X.
2007-04-18Update error message for COPY with a multi-byte delimiter.Bruce Momjian
2007-04-16Add a multi-worker capability to autovacuum. This allows multiple workerAlvaro Herrera
processes to be running simultaneously. Also, now autovacuum processes do not count towards the max_connections limit; they are counted separately from regular processes, and are limited by the new GUC variable autovacuum_max_workers. The launcher now has intelligence to launch workers on each database every autovacuum_naptime seconds, limited only on the max amount of worker slots available. Also, the global worker I/O utilization is limited by the vacuum cost-based delay feature. Workers are "balanced" so that the total I/O consumption does not exceed the established limit. This part of the patch was contributed by ITAGAKI Takahiro. Per discussion.
2007-04-16Make plancache store cursor options so it can pass them to planner duringTom Lane
a replan. I had originally thought this was not necessary, but the new SPI facilities create a path whereby queries planned with non-default options can get into the cache, so it is necessary.
2007-04-16Expose more cursor-related functionality in SPI: specifically, allowTom Lane
access to the planner's cursor-related planning options, and provide new FETCH/MOVE routines that allow access to the full power of those commands. Small refactoring of planner(), pg_plan_query(), and pg_plan_queries() APIs to make it convenient to pass the planning options down from SPI. This is the core-code portion of Pavel Stehule's patch for scrollable cursor support in plpgsql; I'll review and apply the plpgsql changes separately.
2007-04-12Cancel pending fsync requests during WAL replay of DROP DATABASE, per bugTom Lane
report from David Darville. Back-patch as far as 8.1, which may or may not have the problem but it seems a safe change anyway.
2007-04-12RESET SESSION, plus related new DDL commands. Patch from Marko Kreen,Neil Conway
reviewed by Neil Conway. This patch adds the following DDL command variants: RESET SESSION, RESET TEMP, RESET PLANS, CLOSE ALL, and DEALLOCATE ALL. RESET SESSION is intended for use by connection pool software and the like, in order to reset a client session to something close to its initial state. Note that while most of these command variants can be executed inside a transaction block (but are not transaction-aware!), RESET SESSION cannot. While this is inconsistent, it is intended to catch programmer mistakes: RESET SESSION in an open transaction block is probably unintended.
2007-04-08Make CLUSTER MVCC-safe. Heikki LinnakangasTom Lane
2007-04-06Support varlena fields with single-byte headers and unaligned storage.Tom Lane
This commit breaks any code that assumes that the mere act of forming a tuple (without writing it to disk) does not "toast" any fields. While all available regression tests pass, I'm not totally sure that we've fixed every nook and cranny, especially in contrib. Greg Stark with some help from Tom Lane
2007-04-02Support enum data types. Along the way, use macros for the values ofTom Lane
pg_type.typtype whereever practical. Tom Dunstan, with some kibitzing from Tom Lane.
2007-03-29Teach CLUSTER to skip writing WAL if not needed (ie, not using archiving)Tom Lane
--- Simon. Also, code review and cleanup for the previous COPY-no-WAL patches --- Tom.
2007-03-26Allow non-superuser database owners to create procedural languages.Tom Lane
A DBA is allowed to create a language in his database if it's marked "tmpldbacreate" in pg_pltemplate. The factory default is that this is set for all standard trusted languages, but of course a superuser may adjust the settings. In service of this, add the long-foreseen owner column to pg_language; renaming, dropping, and altering owner of a PL now follow normal ownership rules instead of being superuser-only. Jeremy Drake, with some editorialization by Tom Lane.
2007-03-23Fix plancache so that any required replanning is done with the sameTom Lane
search_path that was active when the plan was first made. To do this, improve namespace.c to support a stack of "override" search path settings (we must have a stack since nested replan events are entirely possible). This facility replaces the "special namespace" hack formerly used by CREATE SCHEMA, and should be able to support per-function search path settings as well.
2007-03-22Allow DROP TABLESPACE to succeed (with a warning) if the pg_tblspc symlinkTom Lane
doesn't exist. This allows DROP to be used to clean out the pg_tablespace catalog entry in a situation where a previous DROP attempt failed before committing but after having removed the directories and symlink. Per report from William Garrison. Even though his test case depends on an unrelated bug in PreventTransactionChain, it's certainly possible for this situation to arise due to other problems, eg a system crash at just the right time.