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2010-01-15Introduce Streaming Replication.Heikki Linnakangas
This includes two new kinds of postmaster processes, walsenders and walreceiver. Walreceiver is responsible for connecting to the primary server and streaming WAL to disk, while walsender runs in the primary server and streams WAL from disk to the client. Documentation still needs work, but the basics are there. We will probably pull the replication section to a new chapter later on, as well as the sections describing file-based replication. But let's do that as a separate patch, so that it's easier to see what has been added/changed. This patch also adds a new section to the chapter about FE/BE protocol, documenting the protocol used by walsender/walreceivxer. Bump catalog version because of two new functions, pg_last_xlog_receive_location() and pg_last_xlog_replay_location(), for monitoring the progress of replication. Fujii Masao, with additional hacking by me
2010-01-07Fix (some of the) breakage introduced into query-cancel processing by HS.Tom Lane
It is absolutely not okay to throw an ereport(ERROR) in any random place in the code just because DoingCommandRead is set; interrupting, say, OpenSSL in the midst of its activities is guaranteed to result in heartache. Instead of that, undo the original optimizations that threw away QueryCancelPending anytime we were starting or finishing a command read, and instead discard the cancel request within ProcessInterrupts if we find that there is no HS reason for forcing a cancel and we are DoingCommandRead. In passing, may I once again condemn the practice of changing the code and not fixing the adjacent comment that you just turned into a lie?
2010-01-06Preserve relfilenodes:Bruce Momjian
Add support to pg_dump --binary-upgrade to preserve all relfilenodes, for use by pg_migrator.
2010-01-05Support ALTER TABLESPACE name SET/RESET ( tablespace_options ).Robert Haas
This patch only supports seq_page_cost and random_page_cost as parameters, but it provides the infrastructure to scalably support many more. In particular, we may want to add support for effective_io_concurrency, but I'm leaving that as future work for now. Thanks to Tom Lane for design help and Alvaro Herrera for the review.
2010-01-02Update copyright for the year 2010.Bruce Momjian
2009-12-19Allow read only connections during recovery, known as Hot Standby.Simon Riggs
Enabled by recovery_connections = on (default) and forcing archive recovery using a recovery.conf. Recovery processing now emulates the original transactions as they are replayed, providing full locking and MVCC behaviour for read only queries. Recovery must enter consistent state before connections are allowed, so there is a delay, typically short, before connections succeed. Replay of recovering transactions can conflict and in some cases deadlock with queries during recovery; these result in query cancellation after max_standby_delay seconds have expired. Infrastructure changes have minor effects on normal running, though introduce four new types of WAL record. New test mode "make standbycheck" allows regression tests of static command behaviour on a standby server while in recovery. Typical and extreme dynamic behaviours have been checked via code inspection and manual testing. Few port specific behaviours have been utilised, though primary testing has been on Linux only so far. This commit is the basic patch. Additional changes will follow in this release to enhance some aspects of behaviour, notably improved handling of conflicts, deadlock detection and query cancellation. Changes to VACUUM FULL are also required. Simon Riggs, with significant and lengthy review by Heikki Linnakangas, including streamlined redesign of snapshot creation and two-phase commit. Important contributions from Florian Pflug, Mark Kirkwood, Merlin Moncure, Greg Stark, Gianni Ciolli, Gabriele Bartolini, Hannu Krosing, Robert Haas, Tatsuo Ishii, Hiroyuki Yamada plus support and feedback from many other community members.
2009-12-16Don't unblock SIGQUIT in the SIGQUIT handlerPeter Eisentraut
This was possibly linked to a deadlock-like situation in glibc syslog code invoked by the ereport call in quickdie(). In any case, a signal handler should not unblock its own signal unless there is a specific reason to.
2009-12-16If there is no sigdelset(), define it as a macro.Peter Eisentraut
This removes some duplicate code that recreated the identical workaround when the newer signal API is missing.
2009-12-15Add a hook to let loadable modules get control at ProcessUtility execution,Tom Lane
and use it to extend contrib/pg_stat_statements to track utility commands. Itagaki Takahiro, reviewed by Euler Taveira de Oliveira.
2009-12-15Add an EXPLAIN (BUFFERS) option to show buffer-usage statistics.Robert Haas
This patch also removes buffer-usage statistics from the track_counts output, since this (or the global server statistics) is deemed to be a better interface to this information. Itagaki Takahiro, reviewed by Euler Taveira de Oliveira.
2009-12-11Add large object access control.Itagaki Takahiro
A new system catalog pg_largeobject_metadata manages ownership and access privileges of large objects. KaiGai Kohei, reviewed by Jaime Casanova.
2009-12-09Prevent indirect security attacks via changing session-local state withinTom Lane
an allegedly immutable index function. It was previously recognized that we had to prevent such a function from executing SET/RESET ROLE/SESSION AUTHORIZATION, or it could trivially obtain the privileges of the session user. However, since there is in general no privilege checking for changes of session-local state, it is also possible for such a function to change settings in a way that might subvert later operations in the same session. Examples include changing search_path to cause an unexpected function to be called, or replacing an existing prepared statement with another one that will execute a function of the attacker's choosing. The present patch secures VACUUM, ANALYZE, and CREATE INDEX/REINDEX against these threats, which are the same places previously deemed to need protection against the SET ROLE issue. GUC changes are still allowed, since there are many useful cases for that, but we prevent security problems by forcing a rollback of any GUC change after completing the operation. Other cases are handled by throwing an error if any change is attempted; these include temp table creation, closing a cursor, and creating or deleting a prepared statement. (In 7.4, the infrastructure to roll back GUC changes doesn't exist, so we settle for rejecting changes of "search_path" in these contexts.) Original report and patch by Gurjeet Singh, additional analysis by Tom Lane. Security: CVE-2009-4136
2009-12-07Add exclusion constraints, which generalize the concept of uniqueness toTom Lane
support any indexable commutative operator, not just equality. Two rows violate the exclusion constraint if "row1.col OP row2.col" is TRUE for each of the columns in the constraint. Jeff Davis, reviewed by Robert Haas
2009-12-01Revert due to Tom's concerns:Bruce Momjian
Add ProcessUtility_hook() to handle all DDL to contrib/pg_stat_statements.
2009-12-01ProcessUtility_hook:Bruce Momjian
Add ProcessUtility_hook() to handle all DDL to contrib/pg_stat_statements. Itagaki Takahiro
2009-11-20Add a WHEN clause to CREATE TRIGGER, allowing a boolean expression to beTom Lane
checked to determine whether the trigger should be fired. For BEFORE triggers this is mostly a matter of spec compliance; but for AFTER triggers it can provide a noticeable performance improvement, since queuing of a deferred trigger event and re-fetching of the row(s) at end of statement can be short-circuited if the trigger does not need to be fired. Takahiro Itagaki, reviewed by KaiGai Kohei.
2009-11-16Provide a parenthesized-options syntax for VACUUM, analogous to that recentlyTom Lane
adopted for EXPLAIN. This will allow additional options to be implemented in future without having to make them fully-reserved keywords. The old syntax remains available for existing options, however. Itagaki Takahiro
2009-11-04Add support for invoking parser callback hooks via SPI and in cached plans.Tom Lane
As proof of concept, modify plpgsql to use the hooks. plpgsql is still inserting $n symbols textually, but the "back end" of the parsing process now goes through the ParamRef hook instead of using a fixed parameter-type array, and then execution only fetches actually-referenced parameters, using a hook added to ParamListInfo. Although there's a lot left to be done in plpgsql, this already cures the "if (TG_OP = 'INSERT' and NEW.foo ...)" problem, as illustrated by the changed regression test.
2009-10-26Re-implement EvalPlanQual processing to improve its performance and eliminateTom Lane
a lot of strange behaviors that occurred in join cases. We now identify the "current" row for every joined relation in UPDATE, DELETE, and SELECT FOR UPDATE/SHARE queries. If an EvalPlanQual recheck is necessary, we jam the appropriate row into each scan node in the rechecking plan, forcing it to emit only that one row. The former behavior could rescan the whole of each joined relation for each recheck, which was terrible for performance, and what's much worse could result in duplicated output tuples. Also, the original implementation of EvalPlanQual could not re-use the recheck execution tree --- it had to go through a full executor init and shutdown for every row to be tested. To avoid this overhead, I've associated a special runtime Param with each LockRows or ModifyTable plan node, and arranged to make every scan node below such a node depend on that Param. Thus, by signaling a change in that Param, the EPQ machinery can just rescan the already-built test plan. This patch also adds a prohibition on set-returning functions in the targetlist of SELECT FOR UPDATE/SHARE. This is needed to avoid the duplicate-output-tuple problem. It seems fairly reasonable since the other restrictions on SELECT FOR UPDATE are meant to ensure that there is a unique correspondence between source tuples and result tuples, which an output SRF destroys as much as anything else does.
2009-10-10Split the processing of INSERT/UPDATE/DELETE operations out of execMain.c.Tom Lane
They are now handled by a new plan node type called ModifyTable, which is placed at the top of the plan tree. In itself this change doesn't do much, except perhaps make the handling of RETURNING lists and inherited UPDATEs a tad less klugy. But it is necessary preparation for the intended extension of allowing RETURNING queries inside WITH. Marko Tiikkaja
2009-10-08Remove very ancient tuple-counting infrastructure (IncrRetrieved() andTom Lane
friends). This code has all been ifdef'd out for many years, and doesn't seem to have any prospect of becoming any more useful in the future. EXPLAIN ANALYZE is what people use in practice, and I think if we did want process-wide counters we'd be more likely to put in dtrace events for that than try to resurrect this code. Get rid of it so as to have one less detail to worry about while refactoring execMain.c.
2009-10-05Create an ALTER DEFAULT PRIVILEGES command, which allows users to adjustTom Lane
the privileges that will be applied to subsequently-created objects. Such adjustments are always per owning role, and can be restricted to objects created in particular schemas too. A notable benefit is that users can override the traditional default privilege settings, eg, the PUBLIC EXECUTE privilege traditionally granted by default for functions. Petr Jelinek
2009-09-22Implement the DO statement to support execution of PL code without havingTom Lane
to create a function for it. Procedural languages now have an additional entry point, namely a function to execute an inline code block. This seemed a better design than trying to hide the transient-ness of the code from the PL. As of this patch, only plpgsql has an inline handler, but probably people will soon write handlers for the other standard PLs. In passing, remove the long-dead LANCOMPILER option of CREATE LANGUAGE. Petr Jelinek
2009-09-01Remove flatfiles.c, which is now obsolete.Alvaro Herrera
Recent commits have removed the various uses it was supporting. It was a performance bottleneck, according to bug report #4919 by Lauris Ulmanis; seems it slowed down user creation after a billion users.
2009-09-01Move processing of startup-packet switches and GUC settings into InitPostgres,Tom Lane
to fix the problem that SetClientEncoding needs to be done before InitializeClientEncoding, as reported by Zdenek Kotala. We get at least the small consolation of being able to remove the bizarre API detail that had InitPostgres returning whether user is a superuser.
2009-08-29Remove the use of the pg_auth flat file for client authentication.Tom Lane
(That flat file is now completely useless, but removal will come later.) To do this, postpone client authentication into the startup transaction that's run by InitPostgres. We still collect the startup packet and do SSL initialization (if needed) at the same time we did before. The AuthenticationTimeout is applied separately to startup packet collection and the actual authentication cycle. (This is a bit annoying, since it means a couple extra syscalls; but the signal handling requirements inside and outside a transaction are sufficiently different that it seems best to treat the timeouts as completely independent.) A small security disadvantage is that if the given database name is invalid, this will be reported to the client before any authentication happens. We could work around that by connecting to database "postgres" instead, but consensus seems to be that it's not worth introducing such surprising behavior. Processing of all command-line switches and GUC options received from the client is now postponed until after authentication. This means that PostAuthDelay is much less useful than it used to be --- if you need to investigate problems during InitPostgres you'll have to set PreAuthDelay instead. However, allowing an unauthenticated user to set any GUC options whatever seems a bit too risky, so we'll live with that.
2009-08-28Remove useless code that propagated FrontendProtocol to a backend via aTom Lane
PostgresMain switch. In point of fact, FrontendProtocol is already set in a backend process, since ProcessStartupPacket() is executed inside the backend --- it hasn't been run by the postmaster for many years. And if it were, we'd still certainly want FrontendProtocol to be set before we get as far as PostgresMain, so that startup errors get reported in the right protocol. -v might have some future use in standalone backends, so I didn't go so far as to remove the switch outright. Also, initialize FrontendProtocol to 0 not PG_PROTOCOL_LATEST. The only likely result of presetting it like that is to mask failure-to-set-it mistakes.
2009-07-31Create a multiplexing structure for signals to Postgres child processes.Tom Lane
This patch gets us out from under the Unix limitation of two user-defined signal types. We already had done something similar for signals directed to the postmaster process; this adds multiplexing for signals directed to backends and auxiliary processes (so long as they're connected to shared memory). As proof of concept, replace the former usage of SIGUSR1 and SIGUSR2 for backends with use of the multiplexing mechanism. There are still some hard-wired definitions of SIGUSR1 and SIGUSR2 for other process types, but getting rid of those doesn't seem interesting at the moment. Fujii Masao
2009-07-29Support deferrable uniqueness constraints.Tom Lane
The current implementation fires an AFTER ROW trigger for each tuple that looks like it might be non-unique according to the index contents at the time of insertion. This works well as long as there aren't many conflicts, but won't scale to massive unique-key reassignments. Improving that case is a TODO item. Dean Rasheed
2009-07-28Add system catalog columns pg_constraint.conindid and pg_trigger.tgconstrindid.Tom Lane
conindid is the index supporting a constraint. We can use this not only for unique/primary-key constraints, but also foreign-key constraints, which depend on the unique index that constrains the referenced columns. tgconstrindid is just copied from the constraint's conindid field, or is zero for triggers not associated with constraints. This is mainly intended as infrastructure for upcoming patches, but it has some virtue in itself, since it exposes a relationship that you formerly had to grovel in pg_depend to determine. I simplified one information_schema view accordingly. (There is a pg_dump query that could also use conindid, but I left it alone because it wasn't clear it'd get any faster.)
2009-07-26Extend EXPLAIN to allow generic options to be specified.Tom Lane
The original syntax made it difficult to add options without making them into reserved words. This change parenthesizes the options to avoid that problem, and makes provision for an explicit (and perhaps non-Boolean) value for each option. The original syntax is still supported, but only for the two original options ANALYZE and VERBOSE. As a test case, add a COSTS option that can suppress the planner cost estimates. This may be useful for including EXPLAIN output in the regression tests, which are otherwise unable to cope with cross-platform variations in cost estimates. Robert Haas
2009-07-16Make backend header files C++ safePeter Eisentraut
This alters various incidental uses of C++ key words to use other similar identifiers, so that a C++ compiler won't choke outright. You still (probably) need extern "C" { }; around the inclusion of backend headers. based on a patch by Kurt Harriman <harriman@acm.org> Also add a script cpluspluscheck to check for C++ compatibility in the future. As of right now, this passes without error for me.
2009-06-18Fix a few errors in comments. Patch by Fujii Masao, plus the one inHeikki Linnakangas
visibilitymap.c by me.
2009-06-11Revisit AlterTableCreateToastTable's API once again, hoping to make it whatTom Lane
pg_migrator actually needs and not just a partial solution. We have to be able to specify the OID that the new toast table should be created with.
2009-06-118.4 pgindent run, with new combined Linux/FreeBSD/MinGW typedef listBruce Momjian
provided by Andrew.
2009-05-15Fix all the server-side SIGQUIT handlers (grumble ... why so many identicalTom Lane
copies?) to ensure they really don't run proc_exit/shmem_exit callbacks, as was intended. I broke this behavior recently by installing atexit callbacks without thinking about the one case where we truly don't want to run those callback functions. Noted in an example from Dave Page.
2009-05-07Add an option to AlterTableCreateToastTable() to allow its caller to forceTom Lane
a toast table to be built, even if the sum-of-column-widths calculation indicates one isn't needed. This is needed by pg_migrator because if the old table has a toast table, we have to migrate over the toast table since it might contain some live data, even though subsequent column drops could mean that no recently-added rows could require toasting.
2009-03-27Fix possible failures when a tuplestore switches from in-memory to on-diskTom Lane
mode while callers hold pointers to in-memory tuples. I reported this for the case of nodeWindowAgg's primary scan tuple, but inspection of the code shows that all of the calls in nodeWindowAgg and nodeCtescan are at risk. For the moment, fix it with a rather brute-force approach of copying whenever one of the at-risk callers requests a tuple. Later we might think of some sort of reference-count approach to reduce tuple copying.
2009-02-02Allow reloption names to have qualifiers, initially supporting a TOASTAlvaro Herrera
qualifier, and add support for this in pg_dump. This allows TOAST tables to have user-defined fillfactor, and will also enable us to move the autovacuum parameters to reloptions without taking away the possibility of setting values for TOAST tables.
2009-01-22Support column-level privileges, as required by SQL standard.Tom Lane
Stephen Frost, with help from KaiGai Kohei and others
2009-01-07Update comment associated with 'debug_query_string'.Bruce Momjian
2009-01-02Include a pointer to the query's source text in QueryDesc structs. This isTom Lane
practically free given prior 8.4 changes in plancache and portal management, and it makes it a lot easier for ExecutorStart/Run/End hooks to get at the query text. Extracted from Itagaki Takahiro's pg_stat_statements patch, with minor editorialization.
2009-01-01Update copyright for 2009.Bruce Momjian
2009-01-01Fix an oversight in my patch of a couple weeks ago that ensured a snapshotTom Lane
is available during datatype input in Bind message processing. I put the PopActiveSnapshot() or equivalent just before PortalDefineQuery, which is an unsafe spot for it (in 8.3 and later) because we are carrying a plancache refcount that hasn't yet been assigned to the portal. Any error thrown there would result in leaking the refcount. It's not exactly likely that PopActiveSnapshot would throw an elog, perhaps, but it could happen. Reorder the code and add another comment warning not to do that.
2008-12-19SQL/MED catalog manipulation facilitiesPeter Eisentraut
This doesn't do any remote or external things yet, but it gives modules like plproxy and dblink a standardized and future-proof system for managing their connection information. Martin Pihlak and Peter Eisentraut
2008-12-13Remove pg_plan_queries()'s now-useless needSnapshot parameter. It's uselessTom Lane
in 8.3, too, but I'm not back-patching this change since it would break any extension modules that might be calling that function.
2008-12-13Fix failure to ensure that a snapshot is available to datatype input functionsTom Lane
when they are invoked by the parser. We had been setting up a snapshot at plan time but really it needs to be done earlier, before parse analysis. Per report from Dmitry Koterov. Also fix two related problems discovered while poking at this one: exec_bind_message called datatype input functions without establishing a snapshot, and SET CONSTRAINTS IMMEDIATE could call trigger functions without establishing a snapshot. Backpatch to 8.2. The underlying problem goes much further back, but it is masked in 8.1 and before because we didn't attempt to invoke domain check constraints within datatype input. It would only be exposed if a C-language datatype input function used the snapshot; which evidently none do, or we'd have heard complaints sooner. Since this code has changed a lot over time, a back-patch is hardly risk-free, and so I'm disinclined to patch further than absolutely necessary.
2008-12-09Revert SIGUSR1 multiplexing patch, per Tom's objection.Heikki Linnakangas
2008-12-09Provide support for multiplexing SIGUSR1 signal. The upcoming synchronousHeikki Linnakangas
replication patch needs a signal, but we've already used SIGUSR1 and SIGUSR2 in normal backends. This patch allows reusing SIGUSR1 for that, and for other purposes too if the need arises.
2008-12-04Default values for function argumentsPeter Eisentraut
Pavel Stehule, with some tweaks by Peter Eisentraut