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2015-03-16Support opfamily members in get_object_addressAlvaro Herrera
In the spirit of 890192e99af and 4464303405f: have get_object_address understand individual pg_amop and pg_amproc objects. There is no way to refer to such objects directly in the grammar -- rather, they are almost always considered an integral part of the opfamily that contains them. (The only case that deals with them individually is ALTER OPERATOR FAMILY ADD/DROP, which carries the opfamily address separately and thus does not need it to be part of each added/dropped element's address.) In event triggers it becomes possible to become involved with individual amop/amproc elements, and this commit enables pg_get_object_address to do so as well. To make the overall coding simpler, this commit also slightly changes the get_object_address representation for opclasses and opfamilies: instead of having the AM name in the objargs array, I moved it as the first element of the objnames array. This enables the new code to use objargs for the type names used by pg_amop and pg_amproc. Reviewed by: Stephen Frost
2015-03-11Support default ACLs in get_object_addressAlvaro Herrera
In the spirit of 890192e99af, this time add support for the things living in the pg_default_acl catalog. These are not really "objects", but they show up as such in event triggers. There is no "DROP DEFAULT PRIVILEGES" or similar command, so it doesn't look like the new representation given would be useful anywhere else, so I didn't try to use it outside objectaddress.c. (That might be a bug in itself, but that would be material for another commit.) Reviewed by Stephen Frost.
2015-03-11Support user mappings in get_object_addressAlvaro Herrera
Since commit 72dd233d3ef we were trying to obtain object addressing information in sql_drop event triggers, but that caused failures when the drops involved user mappings. This addition enables that to work again. Naturally, pg_get_object_address can work with these objects now, too. I toyed with the idea of removing DropUserMappingStmt as a node and using DropStmt instead in the DropUserMappingStmt grammar production, but that didn't go very well: for one thing the messages thrown by the specific code are specialized (you get "server not found" if you specify the wrong server, instead of a generic "user mapping for ... not found" which you'd get it we were to merge this with RemoveObjects --- unless we added even more special cases). For another thing, it would require to pass RoleSpec nodes through the objname/objargs representation used by RemoveObjects, which works in isolation, but gets messy when pg_get_object_address is involved. So I dropped this part for now. Reviewed by Stephen Frost.
2015-03-11Require non-NULL pstate for all addRangeTableEntryFor* functions.Robert Haas
Per discussion, it's better to have a consistent coding rule here. Michael Paquier, per a node from Greg Stark referencing an old post from Tom Lane.
2015-03-10Allow named parameters to be specified using => in addition to :=Robert Haas
SQL has standardized on => as the use of to specify named parameters, and we've wanted for many years to support the same syntax ourselves, but this has been complicated by the possible use of => as an operator name. In PostgreSQL 9.0, we began emitting a warning when an operator named => was defined, and in PostgreSQL 9.2, we stopped shipping a =>(text, text) operator as part of hstore. By the time the next major version of PostgreSQL is released, => will have been deprecated for a full five years, so hopefully there won't be too many people still relying on it. We continue to support := for compatibility with previous PostgreSQL releases. Pavel Stehule, reviewed by Petr Jelinek, with a few documentation tweaks by me.
2015-03-09Keep CommitTs module in sync in standby and masterAlvaro Herrera
We allow this module to be turned off on restarts, so a restart time check is enough to activate or deactivate the module; however, if there is a standby replaying WAL emitted from a master which is restarted, but the standby isn't, the state in the standby becomes inconsistent and can easily be crashed. Fix by activating and deactivating the module during WAL replay on parameter change as well as on system start. Problem reported by Fujii Masao in http://www.postgresql.org/message-id/CAHGQGwFhJ3CnHo1CELEfay18yg_RA-XZT-7D8NuWUoYSZ90r4Q@mail.gmail.com Author: Petr Jelínek
2015-03-09Fix crasher bugs in previous commitAlvaro Herrera
ALTER DEFAULT PRIVILEGES was trying to decode the list of roles in the FOR clause as a list of names rather than of RoleSpecs; and the IN clause in CREATE ROLE was doing the same thing. This was evidenced by crashes on some buildfarm machines, though on my platform this doesn't cause a failure by mere chance; I can reproduce the failures only by adding some padding in struct RoleSpecs. Fix by dereferencing those lists as being of RoleSpecs, not string Values.
2015-03-09Allow CURRENT/SESSION_USER to be used in certain commandsAlvaro Herrera
Commands such as ALTER USER, ALTER GROUP, ALTER ROLE, GRANT, and the various ALTER OBJECT / OWNER TO, as well as ad-hoc clauses related to roles such as the AUTHORIZATION clause of CREATE SCHEMA, the FOR clause of CREATE USER MAPPING, and the FOR ROLE clause of ALTER DEFAULT PRIVILEGES can now take the keywords CURRENT_USER and SESSION_USER as user specifiers in place of an explicit user name. This commit also fixes some quite ugly handling of special standards- mandated syntax in CREATE USER MAPPING, which in particular would fail to work in presence of a role named "current_user". The special role specifiers PUBLIC and NONE also have more consistent handling now. Also take the opportunity to add location tracking to user specifiers. Authors: Kyotaro Horiguchi. Heavily reworked by Álvaro Herrera. Reviewed by: Rushabh Lathia, Adam Brightwell, Marti Raudsepp.
2015-03-09Move WAL-related definitions from dbcommands.h to separate header file.Heikki Linnakangas
This makes it easier to write frontend programs that needs to understand the WAL record format of CREATE/DROP DATABASE. dbcommands.h cannot easily be #included in a frontend program, because it pulls in other header files that need backend stuff, but the new dbcommands_xlog.h header file has fewer dependencies.
2015-03-08Code cleanup for REINDEX DATABASE/SCHEMA/SYSTEM.Tom Lane
Fix some minor infelicities. Some of these things were introduced in commit fe263d115a7dd16095b8b8f1e943aff2bb4574d2, and some are older.
2015-03-07Remove rolcatupdatePeter Eisentraut
This role attribute is an ancient PostgreSQL feature, but could only be set by directly updating the system catalogs, and it doesn't have any clearly defined use. Author: Adam Brightwell <[email protected]>
2015-03-03Change many routines to return ObjectAddress rather than OIDAlvaro Herrera
The changed routines are mostly those that can be directly called by ProcessUtilitySlow; the intention is to make the affected object information more precise, in support for future event trigger changes. Originally it was envisioned that the OID of the affected object would be enough, and in most cases that is correct, but upon actually implementing the event trigger changes it turned out that ObjectAddress is more widely useful. Additionally, some command execution routines grew an output argument that's an object address which provides further info about the executed command. To wit: * for ALTER DOMAIN / ADD CONSTRAINT, it corresponds to the address of the new constraint * for ALTER OBJECT / SET SCHEMA, it corresponds to the address of the schema that originally contained the object. * for ALTER EXTENSION {ADD, DROP} OBJECT, it corresponds to the address of the object added to or dropped from the extension. There's no user-visible change in this commit, and no functional change either. Discussion: [email protected] Reviewed-By: Stephen Frost, Andres Freund
2015-03-01Use the typcache to cache constraints for domain types.Tom Lane
Previously, we cached domain constraints for the life of a query, or really for the life of the FmgrInfo struct that was used to invoke domain_in() or domain_check(). But plpgsql (and probably other places) are set up to cache such FmgrInfos for the whole lifespan of a session, which meant they could be enforcing really stale sets of constraints. On the other hand, searching pg_constraint once per query gets kind of expensive too: testing says that as much as half the runtime of a trivial query such as "SELECT 0::domaintype" went into that. To fix this, delegate the responsibility for tracking a domain's constraints to the typcache, which has the infrastructure needed to detect syscache invalidation events that signal possible changes. This not only removes unnecessary repeat reads of pg_constraint, but ensures that we never apply stale constraint data: whatever we use is the current data according to syscache rules. Unfortunately, the current configuration of the system catalogs means we have to flush cached domain-constraint data whenever either pg_type or pg_constraint changes, which happens rather a lot (eg, creation or deletion of a temp table will do it). It might be worth rearranging things to split pg_constraint into two catalogs, of which the domain constraint one would probably be very low-traffic. That's a job for another patch though, and in any case this patch should improve matters materially even with that handicap. This patch makes use of the recently-added memory context reset callback feature to manage the lifespan of domain constraint caches, so that we don't risk deleting a cache that might be in the midst of evaluation. Although this is a bug fix as well as a performance improvement, no back-patch. There haven't been many if any field complaints about stale domain constraint checks, so it doesn't seem worth taking the risk of modifying data structures as basic as MemoryContexts in back branches.
2015-02-27Make CREATE OR REPLACE VIEW internally more consistentAlvaro Herrera
The way that columns are added to a view is by calling AlterTableInternal with special subtype AT_AddColumnToView; but that subtype is changed to AT_AddColumnRecurse by ATPrepAddColumn. This has no visible effect in the current code, since views cannot have inheritance children (thus the recursion step is a no-op) and adding a column to a view is executed identically to doing it to a table; but it does make a difference for future event trigger code keeping track of commands, because the current situation leads to confusing the case with a normal ALTER TABLE ADD COLUMN. Fix the problem by passing a flag to ATPrepAddColumn to prevent it from changing the command subtype. The event trigger code can then properly ignore the subcommand. (We could remove the call to ATPrepAddColumn, since views are never typed, and there is never a need for recursion, which are the two conditions that are checked by ATPrepAddColumn; but it seems more future-proof to keep the call in place.)
2015-02-27Fix table_rewrite event trigger for ALTER TYPE/SET DATA TYPE CASCADEAlvaro Herrera
When a composite type being used in a typed table is modified by way of ALTER TYPE, a table rewrite occurs appearing to come from ALTER TYPE. The existing event_trigger.c code was unable to cope with that and raised a spurious error. The fix is just to accept that command tag for the event, and document this properly. Noted while fooling with deparsing of DDL commands. This appears to be an oversight in commit 618c9430a. Thanks to Mark Wong for documentation wording help.
2015-02-26Reconsider when to wait for WAL flushes/syncrep during commit.Andres Freund
Up to now RecordTransactionCommit() waited for WAL to be flushed (if synchronous_commit != off) and to be synchronously replicated (if enabled), even if a transaction did not have a xid assigned. The primary reason for that is that sequence's nextval() did not assign a xid, but are worthwhile to wait for on commit. This can be problematic because sometimes read only transactions do write WAL, e.g. HOT page prune records. That then could lead to read only transactions having to wait during commit. Not something people expect in a read only transaction. This lead to such strange symptoms as backends being seemingly stuck during connection establishment when all synchronous replicas are down. Especially annoying when said stuck connection is the standby trying to reconnect to allow syncrep again... This behavior also is involved in a rather complicated <= 9.4 bug where the transaction started by catchup interrupt processing waited for syncrep using latches, but didn't get the wakeup because it was already running inside the same overloaded signal handler. Fix the issue here doesn't properly solve that issue, merely papers over the problems. In 9.5 catchup interrupts aren't processed out of signal handlers anymore. To fix all this, make nextval() acquire a top level xid, and only wait for transaction commit if a transaction both acquired a xid and emitted WAL records. If only a xid has been assigned we don't uselessly want to wait just because of writes to temporary/unlogged tables; if only WAL has been written we don't want to wait just because of HOT prunes. The xid assignment in nextval() is unlikely to cause overhead in real-world workloads. For one it only happens SEQ_LOG_VALS/32 values anyway, for another only usage of nextval() without using the result in an insert or similar is affected. Discussion: [email protected], 369698E947874884A77849D8FE3680C2@maumau, 5CF4ABBA67674088B3941894E22A0D25@maumau Per complaint from maumau and Thom Brown Backpatch all the way back; 9.0 doesn't have syncrep, but it seems better to be consistent behavior across all maintained branches.
2015-02-23Support more commands in event triggersAlvaro Herrera
COMMENT, SECURITY LABEL, and GRANT/REVOKE now also fire ddl_command_start and ddl_command_end event triggers, when they operate on database-local objects. Reviewed-By: Michael Paquier, Andres Freund, Stephen Frost
2015-02-22Get rid of multiple applications of transformExpr() to the same tree.Tom Lane
transformExpr() has for many years had provisions to do nothing when applied to an already-transformed expression tree. However, this was always ugly and of dubious reliability, so we'd be much better off without it. The primary historical reason for it was that gram.y sometimes returned multiple links to the same subexpression, which is no longer true as of my BETWEEN fixes. We'd also grown some lazy hacks in CREATE TABLE LIKE (failing to distinguish between raw and already-transformed index specifications) and one or two other places. This patch removes the need for and support for re-transforming already transformed expressions. The index case is dealt with by adding a flag to struct IndexStmt to indicate that it's already been transformed; which has some benefit anyway in that tablecmds.c can now Assert that transformation has happened rather than just assuming. The other main reason was some rather sloppy code for array type coercion, which can be fixed (and its performance improved too) by refactoring. I did leave transformJoinUsingClause() still constructing expressions containing untransformed operator nodes being applied to Vars, so that transformExpr() still has to allow Var inputs. But that's a much narrower, and safer, special case than before, since Vars will never appear in a raw parse tree, and they don't have any substructure to worry about. In passing fix some oversights in the patch that added CREATE INDEX IF NOT EXISTS (missing processing of IndexStmt.if_not_exists). These appear relatively harmless, but still sloppy coding practice.
2015-02-21Use FLEXIBLE_ARRAY_MEMBER in a number of other places.Tom Lane
I think we're about done with this...
2015-02-20Use FLEXIBLE_ARRAY_MEMBER in some more places.Tom Lane
Fix a batch of structs that are only visible within individual .c files. Michael Paquier
2015-02-20Have TRUNCATE update pgstat tuple countersAlvaro Herrera
This works by keeping a per-subtransaction record of the ins/upd/del counters before the truncate, and then resetting them; this record is useful to return to the previous state in case the truncate is rolled back, either in a subtransaction or whole transaction. The state is propagated upwards as subtransactions commit. When the per-table data is sent to the stats collector, a flag indicates to reset the live/dead counters to zero as well. Catalog version bumped due to the change in pgstat format. Author: Alexander Shulgin Discussion: [email protected] Discussion: [email protected] Reviewed-by: Álvaro Herrera, Jim Nasby
2015-02-20Use FLEXIBLE_ARRAY_MEMBER in a bunch more places.Tom Lane
Replace some bogus "x[1]" declarations with "x[FLEXIBLE_ARRAY_MEMBER]". Aside from being more self-documenting, this should help prevent bogus warnings from static code analyzers and perhaps compiler misoptimizations. This patch is just a down payment on eliminating the whole problem, but it gets rid of a lot of easy-to-fix cases. Note that the main problem with doing this is that one must no longer rely on computing sizeof(the containing struct), since the result would be compiler-dependent. Instead use offsetof(struct, lastfield). Autoconf also warns against spelling that offsetof(struct, lastfield[0]). Michael Paquier, review and additional fixes by me.
2015-02-17Fix EXPLAIN output for cases where parent table is excluded by constraints.Tom Lane
The previous coding in EXPLAIN always labeled a ModifyTable node with the name of the target table affected by its first child plan. When originally written, this was necessarily the parent table of the inheritance tree, so everything was unconfusing. But when we added NO INHERIT constraints, it became possible for the parent table to be deleted from the plan by constraint exclusion while still leaving child tables present. This led to the ModifyTable plan node being labeled with the first surviving child, which was deemed confusing. Fix it by retaining the parent table's RT index in a new field in ModifyTable. Etsuro Fujita, reviewed by Ashutosh Bapat and myself
2015-02-03Introduce and use infrastructure for interrupt processing during client reads.Andres Freund
Up to now large swathes of backend code ran inside signal handlers while reading commands from the client, to allow for speedy reaction to asynchronous events. Most prominently shared invalidation and NOTIFY handling. That means that complex code like the starting/stopping of transactions is run in signal handlers... The required code was fragile and verbose, and is likely to contain bugs. That approach also severely limited what could be done while communicating with the client. As the read might be from within openssl it wasn't safely possible to trigger an error, e.g. to cancel a backend in idle-in-transaction state. We did that in some cases, namely fatal errors, nonetheless. Now that FE/BE communication in the backend employs non-blocking sockets and latches to block, we can quite simply interrupt reads from signal handlers by setting the latch. That allows us to signal an interrupted read, which is supposed to be retried after returning from within the ssl library. As signal handlers now only need to set the latch to guarantee timely interrupt processing, remove a fair amount of complicated & fragile code from async.c and sinval.c. We could now actually start to process some kinds of interrupts, like sinval ones, more often that before, but that seems better done separately. This work will hopefully allow to handle cases like being blocked by sending data, interrupting idle transactions and similar to be implemented without too much effort. In addition to allowing getting rid of ImmediateInterruptOK, that is. Author: Andres Freund Reviewed-By: Heikki Linnakangas
2015-02-02Be more careful to not lose sync in the FE/BE protocol.Heikki Linnakangas
If any error occurred while we were in the middle of reading a protocol message from the client, we could lose sync, and incorrectly try to interpret a part of another message as a new protocol message. That will usually lead to an "invalid frontend message" error that terminates the connection. However, this is a security issue because an attacker might be able to deliberately cause an error, inject a Query message in what's supposed to be just user data, and have the server execute it. We were quite careful to not have CHECK_FOR_INTERRUPTS() calls or other operations that could ereport(ERROR) in the middle of processing a message, but a query cancel interrupt or statement timeout could nevertheless cause it to happen. Also, the V2 fastpath and COPY handling were not so careful. It's very difficult to recover in the V2 COPY protocol, so we will just terminate the connection on error. In practice, that's what happened previously anyway, as we lost protocol sync. To fix, add a new variable in pqcomm.c, PqCommReadingMsg, that is set whenever we're in the middle of reading a message. When it's set, we cannot safely ERROR out and continue running, because we might've read only part of a message. PqCommReadingMsg acts somewhat similarly to critical sections in that if an error occurs while it's set, the error handler will force the connection to be terminated, as if the error was FATAL. It's not implemented by promoting ERROR to FATAL in elog.c, like ERROR is promoted to PANIC in critical sections, because we want to be able to use PG_TRY/CATCH to recover and regain protocol sync. pq_getmessage() takes advantage of that to prevent an OOM error from terminating the connection. To prevent unnecessary connection terminations, add a holdoff mechanism similar to HOLD/RESUME_INTERRUPTS() that can be used hold off query cancel interrupts, but still allow die interrupts. The rules on which interrupts are processed when are now a bit more complicated, so refactor ProcessInterrupts() and the calls to it in signal handlers so that the signal handlers always call it if ImmediateInterruptOK is set, and ProcessInterrupts() can decide to not do anything if the other conditions are not met. Reported by Emil Lenngren. Patch reviewed by Noah Misch and Andres Freund. Backpatch to all supported versions. Security: CVE-2015-0244
2015-01-28Clean up range-table building in copy.cStephen Frost
Commit 804b6b6db4dcfc590a468e7be390738f9f7755fb added the build of a range table in copy.c to initialize the EState es_range_table since it can be needed in error paths. Unfortunately, that commit didn't appreciate that some code paths might end up not initializing the rte which is used to build the range table. Fix that and clean up a couple others things along the way- build it only once and don't explicitly set it on the !is_from path as it doesn't make any sense there (cstate is palloc0'd, so this isn't an issue from an initializing standpoint either). The prior commit went back to 9.0, but this only goes back to 9.1 as prior to that the range table build happens immediately after building the RTE and therefore doesn't suffer from this issue. Pointed out by Robert.
2015-01-28Fix column-privilege leak in error-message pathsStephen Frost
While building error messages to return to the user, BuildIndexValueDescription, ExecBuildSlotValueDescription and ri_ReportViolation would happily include the entire key or entire row in the result returned to the user, even if the user didn't have access to view all of the columns being included. Instead, include only those columns which the user is providing or which the user has select rights on. If the user does not have any rights to view the table or any of the columns involved then no detail is provided and a NULL value is returned from BuildIndexValueDescription and ExecBuildSlotValueDescription. Note that, for key cases, the user must have access to all of the columns for the key to be shown; a partial key will not be returned. Further, in master only, do not return any data for cases where row security is enabled on the relation and row security should be applied for the user. This required a bit of refactoring and moving of things around related to RLS- note the addition of utils/misc/rls.c. Back-patch all the way, as column-level privileges are now in all supported versions. This has been assigned CVE-2014-8161, but since the issue and the patch have already been publicized on pgsql-hackers, there's no point in trying to hide this commit.
2015-01-26Fix volatile-safety issue in asyncQueueReadAllNotifications().Tom Lane
The "pos" variable is modified within PG_TRY and then referenced within PG_CATCH, so for strict POSIX conformance it must be marked volatile. Superficially the code looked safe because pos's address was taken, which was sufficient to force it into memory ... but it's not sufficient to ensure that the compiler applies updates exactly where the program text says to. The volatility marking has to extend into a couple of subroutines too, but I think that's probably a good thing because the risk of out-of-order updates is mostly in those subroutines not asyncQueueReadAllNotifications() itself. In principle the compiler could have re-ordered operations such that an error could be thrown while "pos" had an incorrect value. It's unclear how real the risk is here, but for safety back-patch to all active branches.
2015-01-24Clean up some mess in row-security patches.Tom Lane
Fix unsafe coding around PG_TRY in RelationBuildRowSecurity: can't change a variable inside PG_TRY and then use it in PG_CATCH without marking it "volatile". In this case though it seems saner to avoid that by doing a single assignment before entering the TRY block. I started out just intending to fix that, but the more I looked at the row-security code the more distressed I got. This patch also fixes incorrect construction of the RowSecurityPolicy cache entries (there was not sufficient care taken to copy pass-by-ref data into the cache memory context) and a whole bunch of sloppiness around the definition and use of pg_policy.polcmd. You can't use nulls in that column because initdb will mark it NOT NULL --- and I see no particular reason why a null entry would be a good idea anyway, so changing initdb's behavior is not the right answer. The internal value of '\0' wouldn't be suitable in a "char" column either, so after a bit of thought I settled on using '*' to represent ALL. Chasing those changes down also revealed that somebody wasn't paying attention to what the underlying values of ACL_UPDATE_CHR etc really were, and there was a great deal of lackadaiscalness in the catalogs.sgml documentation for pg_policy and pg_policies too. This doesn't pretend to be a complete code review for the row-security stuff, it just fixes the things that were in my face while dealing with the bugs in RelationBuildRowSecurity.
2015-01-22Fix whitespacePeter Eisentraut
2015-01-22adjust ACL owners for REASSIGN and ALTER OWNER TOBruce Momjian
When REASSIGN and ALTER OWNER TO are used, both the object owner and ACL list should be changed from the old owner to the new owner. This patch fixes types, foreign data wrappers, and foreign servers to change their ACL list properly; they already changed owners properly. BACKWARD INCOMPATIBILITY? Report by Alexey Bashtanov
2015-01-19Use abbreviated keys for faster sorting of text datums.Robert Haas
This commit extends the SortSupport infrastructure to allow operator classes the option to provide abbreviated representations of Datums; in the case of text, we abbreviate by taking the first few characters of the strxfrm() blob. If the abbreviated comparison is insufficent to resolve the comparison, we fall back on the normal comparator. This can be much faster than the old way of doing sorting if the first few bytes of the string are usually sufficient to resolve the comparison. There is the potential for a performance regression if all of the strings to be sorted are identical for the first 8+ characters and differ only in later positions; therefore, the SortSupport machinery now provides an infrastructure to abort the use of abbreviation if it appears that abbreviation is producing comparatively few distinct keys. HyperLogLog, a streaming cardinality estimator, is included in this commit and used to make that determination for text. Peter Geoghegan, reviewed by me.
2015-01-16Show sort ordering options in EXPLAIN output.Tom Lane
Up to now, EXPLAIN has contented itself with printing the sort expressions in a Sort or Merge Append plan node. This patch improves that by annotating the sort keys with COLLATE, DESC, USING, and/or NULLS FIRST/LAST whenever nondefault sort ordering options are used. The output is now a reasonably close approximation of an ORDER BY clause equivalent to the plan's ordering. Marius Timmer, Lukas Kreft, and Arne Scheffer; reviewed by Mike Blackwell. Some additional hacking by me.
2015-01-15Rearrange explain.c's API so callers need not embed sizeof(ExplainState).Tom Lane
The folly of the previous arrangement was just demonstrated: there's no convenient way to add fields to ExplainState without breaking ABI, even if callers have no need to touch those fields. Since we might well need to do that again someday in back branches, let's change things so that only explain.c has to have sizeof(ExplainState) compiled into it. This costs one extra palloc() per EXPLAIN operation, which is surely pretty negligible.
2015-01-15Improve performance of EXPLAIN with large range tables.Tom Lane
As of 9.3, ruleutils.c goes to some lengths to ensure that table and column aliases used in its output are unique. Of course this takes more time than was required before, which in itself isn't fatal. However, EXPLAIN was set up so that recalculation of the unique aliases was repeated for each subexpression printed in a plan. That results in O(N^2) time and memory consumption for large plan trees, which did not happen in older branches. Fortunately, the expensive work is the same across a whole plan tree, so there is no need to repeat it; we can do most of the initialization just once per query and re-use it for each subexpression. This buys back most (not all) of the performance loss since 9.2. We need an extra ExplainState field to hold the precalculated deparse context. That's no problem in HEAD, but in the back branches, expanding sizeof(ExplainState) seems risky because third-party extensions might have local variables of that struct type. So, in 9.4 and 9.3, introduce an auxiliary struct to keep sizeof(ExplainState) the same. We should refactor the APIs to avoid such local variables in future, but that's material for a separate HEAD-only commit. Per gripe from Alexey Bashtanov. Back-patch to 9.3 where the issue was introduced.
2015-01-08Fix logging of pages skipped due to pins during vacuum.Andres Freund
The new logging introduced in 35192f06 made the incorrect assumption that scan_all vacuums would always wait for buffer pins; but they only do so if the page actually needs to be frozen. Fix that inaccuracy by removing the difference in log output based on scan_all and just always remove the same message. I chose to keep the split log message from the original commit for now, it seems likely that it'll be of use in the future. Also merge the line about buffer pins in autovacuum's log output into the existing "pages: ..." line. It seems odd to have a separate line about pins, without the "topic: " prefix others have. Also rename the new 'pinned_pages' variable to 'pinskipped_pages' because it actually tracks the number of pages that could *not* be pinned. Discussion: [email protected]
2015-01-08Reject ANALYZE commands during VACUUM FULL or another ANALYZE.Noah Misch
vacuum()'s static variable handling makes it non-reentrant; an ensuing null pointer deference crashed the backend. Back-patch to 9.0 (all supported versions).
2015-01-06Update copyright for 2015Bruce Momjian
Backpatch certain files through 9.0
2015-01-04Add error handling for failing fstat() calls in copy.c.Andres Freund
These calls are pretty much guaranteed not to fail unless something has gone horribly wrong, and even in that case we'd just error out a short time later. But since several code checkers complain about the missing check it seems worthwile to fix it nonetheless. Pointed out by Coverity.
2014-12-30pg_event_trigger_dropped_objects: Add name/args output columnsAlvaro Herrera
These columns can be passed to pg_get_object_address() and used to reconstruct the dropped objects identities in a remote server containing similar objects, so that the drop can be replicated. Reviewed by Stephen Frost, Heikki Linnakangas, Abhijit Menon-Sen, Andres Freund.
2014-12-30Use TypeName to represent type names in certain commandsAlvaro Herrera
In COMMENT, DROP, SECURITY LABEL, and the new pg_get_object_address function, we were representing types as a list of names, same as other objects; but types are special objects that require their own representation to be totally accurate. In the original COMMENT code we had a note about fixing it which was lost in the course of c10575ff005. Change all those places to use TypeName instead, as suggested by that comment. Right now the original coding doesn't cause any bugs, so no backpatch. It is more problematic for proposed future code that operate with object addresses from the SQL interface; type details such as array-ness are lost when working with the degraded representation. Thanks to Petr Jelínek and Dimitri Fontaine for offlist help on finding a solution to a shift/reduce grammar conflict.
2014-12-23Revert "Use a bitmask to represent role attributes"Alvaro Herrera
This reverts commit 1826987a46d079458007b7b6bbcbbd852353adbb. The overall design was deemed unacceptable, in discussion following the previous commit message; we might find some parts of it still salvageable, but I don't want to be on the hook for fixing it, so let's wait until we have a new patch.
2014-12-23Add SQL-callable pg_get_object_addressAlvaro Herrera
This allows access to get_object_address from SQL, which is useful to obtain OID addressing information from data equivalent to that emitted by the parser. This is necessary infrastructure of a project to let replication systems propagate object dropping events to remote servers, where the schema might be different than the server originating the DROP. This patch also adds support for OBJECT_DEFAULT to get_object_address; that is, it is now possible to refer to a column's default value. Catalog version bumped due to the new function. Reviewed by Stephen Frost, Heikki Linnakangas, Robert Haas, Andres Freund, Abhijit Menon-Sen, Adam Brightwell.
2014-12-23Use a bitmask to represent role attributesAlvaro Herrera
The previous representation using a boolean column for each attribute would not scale as well as we want to add further attributes. Extra auxilliary functions are added to go along with this change, to make up for the lost convenience of access of the old representation. Catalog version bumped due to change in catalogs and the new functions. Author: Adam Brightwell, minor tweaks by Álvaro Reviewed by: Stephen Frost, Andres Freund, Álvaro Herrera
2014-12-23get_object_address: separate domain constraints from table constraintsAlvaro Herrera
Apart from enabling comments on domain constraints, this enables a future project to replicate object dropping to remote servers: with the current mechanism there's no way to distinguish between the two types of constraints, so there's no way to know what to drop. Also added support for the domain constraint comments in psql's \dd and pg_dump. Catalog version bumped due to the change in ObjectType enum.
2014-12-19pg_event_trigger_dropped_objects: add behavior flagsAlvaro Herrera
Add "normal" and "original" flags as output columns to the pg_event_trigger_dropped_objects() function. With this it's possible to distinguish which objects, among those listed, need to be explicitely referenced when trying to replicate a deletion. This is necessary so that the list of objects can be pruned to the minimum necessary to replicate the DROP command in a remote server that might have slightly different schema (for instance, TOAST tables and constraints with different names and such.) Catalog version bumped due to change of function definition. Reviewed by: Abhijit Menon-Sen, Stephen Frost, Heikki Linnakangas, Robert Haas.
2014-12-18Use %u to print out BlockNumber variablesAlvaro Herrera
Per Tom Lane
2014-12-18Have VACUUM log number of skipped pages due to pinsAlvaro Herrera
Author: Jim Nasby, some kibitzing by Heikki Linnankangas. Discussion leading to current behavior and precise wording fueled by thoughts from Robert Haas and Andres Freund.
2014-12-18Improve hash_create's API for selecting simple-binary-key hash functions.Tom Lane
Previously, if you wanted anything besides C-string hash keys, you had to specify a custom hashing function to hash_create(). Nearly all such callers were specifying tag_hash or oid_hash; which is tedious, and rather error-prone, since a caller could easily miss the opportunity to optimize by using hash_uint32 when appropriate. Replace this with a design whereby callers using simple binary-data keys just specify HASH_BLOBS and don't need to mess with specific support functions. hash_create() itself will take care of optimizing when the key size is four bytes. This nets out saving a few hundred bytes of code space, and offers a measurable performance improvement in tidbitmap.c (which was not exploiting the opportunity to use hash_uint32 for its 4-byte keys). There might be some wins elsewhere too, I didn't analyze closely. In future we could look into offering a similar optimized hashing function for 8-byte keys. Under this design that could be done in a centralized and machine-independent fashion, whereas getting it right for keys of platform-dependent sizes would've been notationally painful before. For the moment, the old way still works fine, so as not to break source code compatibility for loadable modules. Eventually we might want to remove tag_hash and friends from the exported API altogether, since there's no real need for them to be explicitly referenced from outside dynahash.c. Teodor Sigaev and Tom Lane
2014-12-18Remove odd blank line in comment.Fujii Masao
Etsuro Fujita