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2017-06-21Phase 3 of pgindent updates.Tom Lane
Don't move parenthesized lines to the left, even if that means they flow past the right margin. By default, BSD indent lines up statement continuation lines that are within parentheses so that they start just to the right of the preceding left parenthesis. However, traditionally, if that resulted in the continuation line extending to the right of the desired right margin, then indent would push it left just far enough to not overrun the margin, if it could do so without making the continuation line start to the left of the current statement indent. That makes for a weird mix of indentations unless one has been completely rigid about never violating the 80-column limit. This behavior has been pretty universally panned by Postgres developers. Hence, disable it with indent's new -lpl switch, so that parenthesized lines are always lined up with the preceding left paren. This patch is much less interesting than the first round of indent changes, but also bulkier, so I thought it best to separate the effects. Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
2017-06-21Phase 2 of pgindent updates.Tom Lane
Change pg_bsd_indent to follow upstream rules for placement of comments to the right of code, and remove pgindent hack that caused comments following #endif to not obey the general rule. Commit e3860ffa4dd0dad0dd9eea4be9cc1412373a8c89 wasn't actually using the published version of pg_bsd_indent, but a hacked-up version that tried to minimize the amount of movement of comments to the right of code. The situation of interest is where such a comment has to be moved to the right of its default placement at column 33 because there's code there. BSD indent has always moved right in units of tab stops in such cases --- but in the previous incarnation, indent was working in 8-space tab stops, while now it knows we use 4-space tabs. So the net result is that in about half the cases, such comments are placed one tab stop left of before. This is better all around: it leaves more room on the line for comment text, and it means that in such cases the comment uniformly starts at the next 4-space tab stop after the code, rather than sometimes one and sometimes two tabs after. Also, ensure that comments following #endif are indented the same as comments following other preprocessor commands such as #else. That inconsistency turns out to have been self-inflicted damage from a poorly-thought-through post-indent "fixup" in pgindent. This patch is much less interesting than the first round of indent changes, but also bulkier, so I thought it best to separate the effects. Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
2017-06-21Restart logical replication launcher when killedPeter Eisentraut
Author: Yugo Nagata <nagata@sraoss.co.jp>
2017-06-21Initial pgindent run with pg_bsd_indent version 2.0.Tom Lane
The new indent version includes numerous fixes thanks to Piotr Stefaniak. The main changes visible in this commit are: * Nicer formatting of function-pointer declarations. * No longer unexpectedly removes spaces in expressions using casts, sizeof, or offsetof. * No longer wants to add a space in "struct structname *varname", as well as some similar cases for const- or volatile-qualified pointers. * Declarations using PG_USED_FOR_ASSERTS_ONLY are formatted more nicely. * Fixes bug where comments following declarations were sometimes placed with no space separating them from the code. * Fixes some odd decisions for comments following case labels. * Fixes some cases where comments following code were indented to less than the expected column 33. On the less good side, it now tends to put more whitespace around typedef names that are not listed in typedefs.list. This might encourage us to put more effort into typedef name collection; it's not really a bug in indent itself. There are more changes coming after this round, having to do with comment indentation and alignment of lines appearing within parentheses. I wanted to limit the size of the diffs to something that could be reviewed without one's eyes completely glazing over, so it seemed better to split up the changes as much as practical. Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
2017-06-13Re-run pgindent.Tom Lane
This is just to have a clean base state for testing of Piotr Stefaniak's latest version of FreeBSD indent. I fixed up a couple of places where pgindent would have changed format not-nicely. perltidy not included. Discussion: https://postgr.es/m/VI1PR03MB119959F4B65F000CA7CD9F6BF2CC0@VI1PR03MB1199.eurprd03.prod.outlook.com
2017-06-08Use standard interrupt handling in logical replication launcher.Andres Freund
Previously the exit handling was only able to exit from within the main loop, and not from within the backend code it calls. Fix that by using the standard die() SIGTERM handler, and adding the necessary CHECK_FOR_INTERRUPTS() call. This requires adding yet another process-type-specific branch to ProcessInterrupts(), which hints that we probably should generalize that handling. But that's work for another day. Author: Petr Jelinek Reviewed-By: Andres Freund Discussion: https://postgr.es/m/fe072153-babd-3b5d-8052-73527a6eb657@2ndquadrant.com
2017-06-05Unify SIGHUP handling between normal and walsender backends.Andres Freund
Because walsender and normal backends share the same main loop it's problematic to have two different flag variables, set in signal handlers, indicating a pending configuration reload. Only certain walsender commands reach code paths checking for the variable (START_[LOGICAL_]REPLICATION, CREATE_REPLICATION_SLOT ... LOGICAL, notably not base backups). This is a bug present since the introduction of walsender, but has gotten worse in releases since then which allow walsender to do more. A later patch, not slated for v10, will similarly unify SIGHUP handling in other types of processes as well. Author: Petr Jelinek, Andres Freund Reviewed-By: Michael Paquier Discussion: https://postgr.es/m/20170423235941.qosiuoyqprq4nu7v@alap3.anarazel.de Backpatch: 9.2-, bug is present since 9.0
2017-06-04Disallow CREATE INDEX if table is already in use in current session.Tom Lane
If we allow this, whatever outer command has the table open will not know about the new index and may fail to update it as needed, as shown in a report from Laurenz Albe. We already had such a prohibition in place for ALTER TABLE, but the CREATE INDEX syntax missed the check. Fixing it requires an API change for DefineIndex(), which conceivably would break third-party extensions if we were to back-patch it. Given how long this problem has existed without being noticed, fixing it in the back branches doesn't seem worth that risk. Discussion: https://postgr.es/m/A737B7A37273E048B164557ADEF4A58B53A4DC9A@ntex2010i.host.magwien.gv.at
2017-06-02Fix signal handling in logical replication workersPeter Eisentraut
The logical replication worker processes now use the normal die() handler for SIGTERM and CHECK_FOR_INTERRUPTS() instead of custom code. One problem before was that the apply worker would not exit promptly when a subscription was dropped, which could lead to deadlocks. Author: Petr Jelinek <petr.jelinek@2ndquadrant.com> Reported-by: Masahiko Sawada <sawada.mshk@gmail.com>
2017-05-17Post-PG 10 beta1 pgindent runBruce Momjian
perltidy run not included.
2017-04-10Improve castNode notation by introducing list-extraction-specific variants.Tom Lane
This extends the castNode() notation introduced by commit 5bcab1114 to provide, in one step, extraction of a list cell's pointer and coercion to a concrete node type. For example, "lfirst_node(Foo, lc)" is the same as "castNode(Foo, lfirst(lc))". Almost half of the uses of castNode that have appeared so far include a list extraction call, so this is pretty widely useful, and it saves a few more keystrokes compared to the old way. As with the previous patch, back-patch the addition of these macros to pg_list.h, so that the notation will be available when back-patching. Patch by me, after an idea of Andrew Gierth's. Discussion: https://postgr.es/m/14197.1491841216@sss.pgh.pa.us
2017-04-06Remove dead code and fix comments in fast-path function handling.Heikki Linnakangas
HandleFunctionRequest() is no longer responsible for reading the protocol message from the client, since commit 2b3a8b20c2. Fix the outdated comments. HandleFunctionRequest() now always returns 0, because the code that used to return EOF was moved in 2b3a8b20c2. Therefore, the caller no longer needs to check the return value. Reported by Andres Freund. Backpatch to all supported versions, even though this doesn't have any user-visible effect, to make backporting future patches in this area easier. Discussion: https://www.postgresql.org/message-id/20170405010525.rt5azbya5fkbhvrx@alap3.anarazel.de
2017-04-05Spelling mistake in comment in utility.cSimon Riggs
2017-04-01Fix two undocumented parameters to functions from ENR patch.Kevin Grittner
On ProcessUtility document the parameter, to match others. On CreateCachedPlan drop the queryEnv parameter. It was not referenced within the function, and had been added on the assumption that with some unknown future usage of QueryEnvironment it might be useful to do something there. We have avoided other "just in case" implementation of unused paramters, so drop it here. Per gripe from Tom Lane
2017-03-31Add infrastructure to support EphemeralNamedRelation references.Kevin Grittner
A QueryEnvironment concept is added, which allows new types of objects to be passed into queries from parsing on through execution. At this point, the only thing implemented is a collection of EphemeralNamedRelation objects -- relations which can be referenced by name in queries, but do not exist in the catalogs. The only type of ENR implemented is NamedTuplestore, but provision is made to add more types fairly easily. An ENR can carry its own TupleDesc or reference a relation in the catalogs by relid. Although these features can be used without SPI, convenience functions are added to SPI so that ENRs can easily be used by code run through SPI. The initial use of all this is going to be transition tables in AFTER triggers, but that will be added to each PL as a separate commit. An incidental effect of this patch is to produce a more informative error message if an attempt is made to modify the contents of a CTE from a referencing DML statement. No tests previously covered that possibility, so one is added. Kevin Grittner and Thomas Munro Reviewed by Heikki Linnakangas, David Fetter, and Thomas Munro with valuable comments and suggestions from many others
2017-03-28Cast result of copyObject() to correct typePeter Eisentraut
copyObject() is declared to return void *, which allows easily assigning the result independent of the input, but it loses all type checking. If the compiler supports typeof or something similar, cast the result to the input type. This creates a greater amount of type safety. In some cases, where the result is assigned to a generic type such as Node * or Expr *, new casts are now necessary, but in general casts are now unnecessary in the normal case and indicate that something unusual is happening. Reviewed-by: Mark Dilger <hornschnorter@gmail.com>
2017-03-26Add missing breakAlvaro Herrera
Noticed by Coverity
2017-03-25Add missing breakPeter Eisentraut
Reported-by: Mark Kirkwood <mark.kirkwood@catalyst.net.nz>
2017-03-24Implement multivariate n-distinct coefficientsAlvaro Herrera
Add support for explicitly declared statistic objects (CREATE STATISTICS), allowing collection of statistics on more complex combinations that individual table columns. Companion commands DROP STATISTICS and ALTER STATISTICS ... OWNER TO / SET SCHEMA / RENAME are added too. All this DDL has been designed so that more statistic types can be added later on, such as multivariate most-common-values and multivariate histograms between columns of a single table, leaving room for permitting columns on multiple tables, too, as well as expressions. This commit only adds support for collection of n-distinct coefficient on user-specified sets of columns in a single table. This is useful to estimate number of distinct groups in GROUP BY and DISTINCT clauses; estimation errors there can cause over-allocation of memory in hashed aggregates, for instance, so it's a worthwhile problem to solve. A new special pseudo-type pg_ndistinct is used. (num-distinct estimation was deemed sufficiently useful by itself that this is worthwhile even if no further statistic types are added immediately; so much so that another version of essentially the same functionality was submitted by Kyotaro Horiguchi: https://postgr.es/m/20150828.173334.114731693.horiguchi.kyotaro@lab.ntt.co.jp though this commit does not use that code.) Author: Tomas Vondra. Some code rework by Álvaro. Reviewed-by: Dean Rasheed, David Rowley, Kyotaro Horiguchi, Jeff Janes, Ideriha Takeshi Discussion: https://postgr.es/m/543AFA15.4080608@fuzzy.cz https://postgr.es/m/20170320190220.ixlaueanxegqd5gr@alvherre.pgsql
2017-03-23ICU supportPeter Eisentraut
Add a column collprovider to pg_collation that determines which library provides the collation data. The existing choices are default and libc, and this adds an icu choice, which uses the ICU4C library. The pg_locale_t type is changed to a union that contains the provider-specific locale handles. Users of locale information are changed to look into that struct for the appropriate handle to use. Also add a collversion column that records the version of the collation when it is created, and check at run time whether it is still the same. This detects potentially incompatible library upgrades that can corrupt indexes and other structures. This is currently only supported by ICU-provided collations. initdb initializes the default collation set as before from the `locale -a` output but also adds all available ICU locales with a "-x-icu" appended. Currently, ICU-provided collations can only be explicitly named collations. The global database locales are still always libc-provided. ICU support is enabled by configure --with-icu. Reviewed-by: Thomas Munro <thomas.munro@enterprisedb.com> Reviewed-by: Andreas Karlsson <andreas@proxel.se>
2017-03-23Allow for parallel execution whenever ExecutorRun() is done only once.Robert Haas
Previously, it was unsafe to execute a plan in parallel if ExecutorRun() might be called with a non-zero row count. However, it's quite easy to fix things up so that we can support that case, provided that it is known that we will never call ExecutorRun() a second time for the same QueryDesc. Add infrastructure to signal this, and cross-checks to make sure that a caller who claims this is true doesn't later reneg. While that pattern never happens with queries received directly from a client -- there's no way to know whether multiple Execute messages will be sent unless the first one requests all the rows -- it's pretty common for queries originating from procedural languages, which often limit the result to a single tuple or to a user-specified number of tuples. This commit doesn't actually enable parallelism in any additional cases, because currently none of the places that would be able to benefit from this infrastructure pass CURSOR_OPT_PARALLEL_OK in the first place, but it makes it much more palatable to pass CURSOR_OPT_PARALLEL_OK in places where we currently don't, because it eliminates some cases where we'd end up having to run the parallel plan serially. Patch by me, based on some ideas from Rafia Sabih and corrected by Rafia Sabih based on feedback from Dilip Kumar and myself. Discussion: http://postgr.es/m/CA+TgmobXEhvHbJtWDuPZM9bVSLiTj-kShxQJ2uM5GPDze9fRYA@mail.gmail.com
2017-03-23Logical replication support for initial data copyPeter Eisentraut
Add functionality for a new subscription to copy the initial data in the tables and then sync with the ongoing apply process. For the copying, add a new internal COPY option to have the COPY source data provided by a callback function. The initial data copy works on the subscriber by receiving COPY data from the publisher and then providing it locally into a COPY that writes to the destination table. A WAL receiver can now execute full SQL commands. This is used here to obtain information about tables and publications. Several new options were added to CREATE and ALTER SUBSCRIPTION to control whether and when initial table syncing happens. Change pg_dump option --no-create-subscription-slots to --no-subscription-connect and use the new CREATE SUBSCRIPTION ... NOCONNECT option for that. Author: Petr Jelinek <petr.jelinek@2ndquadrant.com> Tested-by: Erik Rijkers <er@xs4all.nl>
2017-03-03Disallow CREATE/DROP SUBSCRIPTION in transaction blockPeter Eisentraut
Disallow CREATE SUBSCRIPTION and DROP SUBSCRIPTION in a transaction block when the replication slot is to be created or dropped, since that cannot be rolled back. based on patch by Masahiko Sawada <sawada.mshk@gmail.com>
2017-02-23Consistently declare timestamp variables as TimestampTz.Tom Lane
Twiddle the replication-related code so that its timestamp variables are declared TimestampTz, rather than the uninformative "int64" that was previously used for meant-to-be-always-integer timestamps. This resolves the int64-vs-TimestampTz declaration inconsistencies introduced by commit 7c030783a, though in the opposite direction to what was originally suggested. This required including datatype/timestamp.h in a couple more places than before. I decided it would be a good idea to slim down that header by not having it pull in <float.h> etc, as those headers are no longer at all relevant to its purpose. Unsurprisingly, a small number of .c files turn out to have been depending on those inclusions, so add them back in the .c files as needed. Discussion: https://postgr.es/m/26788.1487455319@sss.pgh.pa.us Discussion: https://postgr.es/m/27694.1487456324@sss.pgh.pa.us
2017-02-15Add CREATE COLLATION IF NOT EXISTS clausePeter Eisentraut
The core of the functionality was already implemented when pg_import_system_collations was added. This just exposes it as an option in the SQL command.
2017-01-27Improve comments about ProcessUtility's queryString parameter.Tom Lane
Per discussion with Craig Ringer.
2017-01-26Use castNode() in a bunch of statement-list-related code.Tom Lane
When I wrote commit ab1f0c822, I really missed the castNode() macro that Peter E. had proposed shortly before. This back-fills the uses I would have put it to. It's probably not all that significant, but there are more assertions here than there were before, and conceivably they will help catch any bugs associated with those representation changes. I left behind a number of usages like "(Query *) copyObject(query_var)". Those could have been converted as well, but Peter has proposed another notational improvement that would handle copyObject cases automatically, so I let that be for now.
2017-01-26Add castNode(type, ptr) for safe casting between NodeTag based types.Andres Freund
The new function allows to cast from one NodeTag based type to another, while asserting that the conversion is valid. This replaces the common pattern of doing a cast and a Assert(IsA(ptr, type)) close-by. As this seems likely to be used pervasively, we decided to backpatch this change the addition of this macro. Otherwise backpatched fixes are more likely not to work on back-branches. On branches before 9.6, where we do not yet rely on inline functions being available, the type assertion is only performed if PG_USE_INLINE support is detected. The cast obviously is performed regardless. For the benefit of verifying the macro compiles in the back-branches, this commit contains a single use of the new macro. On master, a somewhat larger conversion will be committed separately. Author: Peter Eisentraut and Andres Freund Reviewed-By: Tom Lane Discussion: https://postgr.es/m/c5d387d9-3440-f5e0-f9d4-71d53b9fbe52@2ndquadrant.com Backpatch: 9.2-
2017-01-24Add a new DestReceiver for printing tuples without catalog access.Robert Haas
If you create a DestReciver of type DestRemote and try to use it from a replication connection that is not bound to a specific daabase, or any other hypothetical type of backend that is not bound to a specific database, it will fail because it doesn't have a pg_proc catalog to look up properties of the types being printed. In general, that's an unavoidable problem, but we can hardwire the properties of a few builtin types in order to support utility commands. This new DestReceiver of type DestRemoteSimple does just that. Patch by me, reviewed by Michael Paquier. Discussion: http://postgr.es/m/CA+TgmobNo4qz06wHEmy9DszAre3dYx-WNhHSCbU9SAwf+9Ft6g@mail.gmail.com
2017-01-20Logical replicationPeter Eisentraut
- Add PUBLICATION catalogs and DDL - Add SUBSCRIPTION catalog and DDL - Define logical replication protocol and output plugin - Add logical replication workers From: Petr Jelinek <petr@2ndquadrant.com> Reviewed-by: Steve Singer <steve@ssinger.info> Reviewed-by: Andres Freund <andres@anarazel.de> Reviewed-by: Erik Rijkers <er@xs4all.nl> Reviewed-by: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
2017-01-19Avoid core dump for empty prepared statement in an aborted transaction.Tom Lane
Brown-paper-bag bug in commit ab1f0c822: the old code here coped with null CachedPlanSource.raw_parse_tree, the new code not so much. Per report from Dave Cramer. No regression test, because our core testing infrastructure doesn't provide any easy way to exercise this path. Fortunately, the JDBC crew test it regularly. Discussion: https://postgr.es/m/CADK3HH+Ug3xCysKqw_dZOnaNnytZ1Rh5yP05hjO-e4NoyRxVvA@mail.gmail.com
2017-01-14Change representation of statement lists, and add statement location info.Tom Lane
This patch makes several changes that improve the consistency of representation of lists of statements. It's always been the case that the output of parse analysis is a list of Query nodes, whatever the types of the individual statements in the list. This patch brings similar consistency to the outputs of raw parsing and planning steps: * The output of raw parsing is now always a list of RawStmt nodes; the statement-type-dependent nodes are one level down from that. * The output of pg_plan_queries() is now always a list of PlannedStmt nodes, even for utility statements. In the case of a utility statement, "planning" just consists of wrapping a CMD_UTILITY PlannedStmt around the utility node. This list representation is now used in Portal and CachedPlan plan lists, replacing the former convention of intermixing PlannedStmts with bare utility-statement nodes. Now, every list of statements has a consistent head-node type depending on how far along it is in processing. This allows changing many places that formerly used generic "Node *" pointers to use a more specific pointer type, thus reducing the number of IsA() tests and casts needed, as well as improving code clarity. Also, the post-parse-analysis representation of DECLARE CURSOR is changed so that it looks more like EXPLAIN, PREPARE, etc. That is, the contained SELECT remains a child of the DeclareCursorStmt rather than getting flipped around to be the other way. It's now true for both Query and PlannedStmt that utilityStmt is non-null if and only if commandType is CMD_UTILITY. That allows simplifying a lot of places that were testing both fields. (I think some of those were just defensive programming, but in many places, it was actually necessary to avoid confusing DECLARE CURSOR with SELECT.) Because PlannedStmt carries a canSetTag field, we're also able to get rid of some ad-hoc rules about how to reconstruct canSetTag for a bare utility statement; specifically, the assumption that a utility is canSetTag if and only if it's the only one in its list. While I see no near-term need for relaxing that restriction, it's nice to get rid of the ad-hocery. The API of ProcessUtility() is changed so that what it's passed is the wrapper PlannedStmt not just the bare utility statement. This will affect all users of ProcessUtility_hook, but the changes are pretty trivial; see the affected contrib modules for examples of the minimum change needed. (Most compilers should give pointer-type-mismatch warnings for uncorrected code.) There's also a change in the API of ExplainOneQuery_hook, to pass through cursorOptions instead of expecting hook functions to know what to pick. This is needed because of the DECLARE CURSOR changes, but really should have been done in 9.6; it's unlikely that any extant hook functions know about using CURSOR_OPT_PARALLEL_OK. Finally, teach gram.y to save statement boundary locations in RawStmt nodes, and pass those through to Query and PlannedStmt nodes. This allows more intelligent handling of cases where a source query string contains multiple statements. This patch doesn't actually do anything with the information, but a follow-on patch will. (Passing this information through cleanly is the true motivation for these changes; while I think this is all good cleanup, it's unlikely we'd have bothered without this end goal.) catversion bump because addition of location fields to struct Query affects stored rules. This patch is by me, but it owes a good deal to Fabien Coelho who did a lot of preliminary work on the problem, and also reviewed the patch. Discussion: https://postgr.es/m/alpine.DEB.2.20.1612200926310.29821@lancre
2017-01-03Update copyright via script for 2017Bruce Momjian
2016-12-22Use TSConfigRelationId in AlterTSConfiguration()Stephen Frost
When we are altering a text search configuration, we are getting the tuple from pg_ts_config and using its OID, so use TSConfigRelationId when invoking any post-alter hooks and setting the object address. Further, in the functions called from AlterTSConfiguration(), we're saving information about the command via EventTriggerCollectAlterTSConfig(), so we should be setting commandCollected to true. Also add a regression test to test_ddl_deparse for ALTER TEXT SEARCH CONFIGURATION. Author: Artur Zakirov, a few additional comments by me Discussion: https://www.postgresql.org/message-id/57a71eba-f2c7-e7fd-6fc0-2126ec0b39bd%40postgrespro.ru Back-patch the fix for the InvokeObjectPostAlterHook() call to 9.3 where it was introduced, and the fix for the ObjectAddressSet() call and setting commandCollected to true to 9.5 where those changes to ProcessUtilitySlow() were introduced.
2016-12-12Add support for temporary replication slotsPeter Eisentraut
This allows creating temporary replication slots that are removed automatically at the end of the session or on error. From: Petr Jelinek <petr.jelinek@2ndquadrant.com>
2016-12-07Implement table partitioning.Robert Haas
Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-11-17Remove or reduce verbosity of some debug messages.Robert Haas
The debug messages that merely print StartTransactionCommand, CommitTransactionCommand, ProcessUtilty, or ProcessQuery with no additional details seem to be useless. Get rid of them. The transaction status messages produced by ShowTransactionState are occasionally useful, but they are extremely verbose, producing multiple lines of log output every time they fire, which can happens multiple times per transaction. So, reduce the level to DEBUG5; avoid emitting an extra line just to explain which debug point is at issue; and tighten up the rest of the message so it doesn't use quite so much horizontal space. With these changes, it's possible to run a somewhat busy system with a log level even as high as DEBUG4, whereas previously anything above DEBUG2 would flood the log with output that probably wasn't really all that useful.
2016-11-15Account for catalog snapshot in PGXACT->xmin updates.Tom Lane
The CatalogSnapshot was not plugged into SnapshotResetXmin()'s accounting for whether MyPgXact->xmin could be cleared or advanced. In normal transactions this was masked by the fact that the transaction snapshot would be older, but during backend startup and certain utility commands it was possible to re-use the CatalogSnapshot after MyPgXact->xmin had been cleared, meaning that recently-deleted rows could be pruned even though this snapshot could still see them, causing unexpected catalog lookup failures. This effect appears to be the explanation for a recent failure on buildfarm member piculet. To fix, add the CatalogSnapshot to the RegisteredSnapshots heap whenever it is valid. In the previous logic, it was possible for the CatalogSnapshot to remain valid across waits for client input, but with this change that would mean it delays advance of global xmin in cases where it did not before. To avoid possibly causing new table-bloat problems with clients that sit idle for long intervals, add code to invalidate the CatalogSnapshot before waiting for client input. (When the backend is busy, it's unlikely that the CatalogSnapshot would be the oldest snap for very long, so we don't worry about forcing early invalidation of it otherwise.) In passing, remove the CatalogSnapshotStale flag in favor of using "CatalogSnapshot != NULL" to represent validity, as we do for the other special snapshots in snapmgr.c. And improve some obsolete comments. No regression test because I don't know a deterministic way to cause this failure. But the stress test shown in the original discussion provokes "cache lookup failed for relation 1255" within a few dozen seconds for me. Back-patch to 9.4 where MVCC catalog scans were introduced. (Note: it's quite easy to produce similar failures with the same test case in branches before 9.4. But MVCC catalog scans were supposed to fix that.) Discussion: <16447.1478818294@sss.pgh.pa.us>
2016-10-19Make getrusage() output a little more readablePeter Eisentraut
Reviewed-by: Robert Haas <robertmhaas@gmail.com> Reviewed-by: Peter Geoghegan <pg@heroku.com>
2016-10-11Drop server support for FE/BE protocol version 1.0.Tom Lane
While this isn't a lot of code, it's been essentially untestable for a very long time, because libpq doesn't support anything older than protocol 2.0, and has not since release 6.3. There's no reason to believe any other client-side code still uses that protocol, either. Discussion: <2661.1475849167@sss.pgh.pa.us>
2016-09-06Add location field to DefElemPeter Eisentraut
Add a location field to the DefElem struct, used to parse many utility commands. Update various error messages to supply error position information. To propogate the error position information in a more systematic way, create a ParseState in standard_ProcessUtility() and pass that to interested functions implementing the utility commands. This seems better than passing the query string and then reassembling a parse state ad hoc, which violates the encapsulation of the ParseState type. Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com>
2016-09-05Relax transactional restrictions on ALTER TYPE ... ADD VALUE.Tom Lane
To prevent possibly breaking indexes on enum columns, we must keep uncommitted enum values from getting stored in tables, unless we can be sure that any such column is new in the current transaction. Formerly, we enforced this by disallowing ALTER TYPE ... ADD VALUE from being executed at all in a transaction block, unless the target enum type had been created in the current transaction. This patch removes that restriction, and instead insists that an uncommitted enum value can't be referenced unless it belongs to an enum type created in the same transaction as the value. Per discussion, this should be a bit less onerous. It does require each function that could possibly return a new enum value to SQL operations to check this restriction, but there aren't so many of those that this seems unmaintainable. Andrew Dunstan and Tom Lane Discussion: <4075.1459088427@sss.pgh.pa.us>
2016-08-27Add macros to make AllocSetContextCreate() calls simpler and safer.Tom Lane
I found that half a dozen (nearly 5%) of our AllocSetContextCreate calls had typos in the context-sizing parameters. While none of these led to especially significant problems, they did create minor inefficiencies, and it's now clear that expecting people to copy-and-paste those calls accurately is not a great idea. Let's reduce the risk of future errors by introducing single macros that encapsulate the common use-cases. Three such macros are enough to cover all but two special-purpose contexts; those two calls can be left as-is, I think. While this patch doesn't in itself improve matters for third-party extensions, it doesn't break anything for them either, and they can gradually adopt the simplified notation over time. In passing, change TopMemoryContext to use the default allocation parameters. Formerly it could only be extended 8K at a time. That was probably reasonable when this code was written; but nowadays we create many more contexts than we did then, so that it's not unusual to have a couple hundred K in TopMemoryContext, even without considering various dubious code that sticks other things there. There seems no good reason not to let it use growing blocks like most other contexts. Back-patch to 9.6, mostly because that's still close enough to HEAD that it's easy to do so, and keeping the branches in sync can be expected to avoid some future back-patching pain. The bugs fixed by these changes don't seem to be significant enough to justify fixing them further back. Discussion: <21072.1472321324@sss.pgh.pa.us>
2016-08-07Fix TOAST access failure in RETURNING queries.Tom Lane
Discussion of commit 3e2f3c2e4 exposed a problem that is of longer standing: since we don't detoast data while sticking it into a portal's holdStore for PORTAL_ONE_RETURNING and PORTAL_UTIL_SELECT queries, and we release the query's snapshot as soon as we're done loading the holdStore, later readout of the holdStore can do TOAST fetches against data that can no longer be seen by any of the session's live snapshots. This means that a concurrent VACUUM could remove the TOAST data before we can fetch it. Commit 3e2f3c2e4 exposed the problem by showing that sometimes we had *no* live snapshots while fetching TOAST data, but we'd be at risk anyway. I believe this code was all right when written, because our management of a session's exposed xmin was such that the TOAST references were safe until end of transaction. But that's no longer true now that we can advance or clear our PGXACT.xmin intra-transaction. To fix, copy the query's snapshot during FillPortalStore() and save it in the Portal; release it only when the portal is dropped. This essentially implements a policy that we must hold a relevant snapshot whenever we access potentially-toasted data. We had already come to that conclusion in other places, cf commits 08e261cbc94ce9a7 and ec543db77b6b72f2. I'd have liked to add a regression test case for this, but I didn't see a way to make one that's not unreasonably bloated; it seems to require returning a toasted value to the client, and those will be big. In passing, improve PortalRunUtility() so that it positively verifies that its ending PopActiveSnapshot() call will pop the expected snapshot, removing a rather shaky assumption about which utility commands might do their own PopActiveSnapshot(). There's no known bug here, but now that we're actively referencing the snapshot it's almost free to make this code a bit more bulletproof. We might want to consider back-patching something like this into older branches, but it would be prudent to let it prove itself more in HEAD beforehand. Discussion: <87vazemeda.fsf@credativ.de>
2016-07-10Revert "Add some temporary code to record stack usage at server process exit."Tom Lane
This reverts commit 88cf37d2a86d5b66380003d7c3384530e3f91e40 as well as follow-on commits ea9c4a16d5ad88a1d28d43ef458e3209b53eb106 and c57562725d219c4249b82f4a4fb5aaeee3ae0d53. We've learned about as much as we can from the buildfarm.
2016-07-08Add more temporary code to record stack usage at server process exit.Tom Lane
After a look at preliminary results from commit 88cf37d2a86d5b66, I realized it'd be a good idea to spew out the maximum depth measurement seen by check_stack_depth. So add some quick-n-dirty code to do that. Like the previous commit, this will be reverted once we've gathered a set of buildfarm runs with it.
2016-06-06Stop the executor if no more tuples can be sent from worker to leader.Robert Haas
If a Gather node has read as many tuples as it needs (for example, due to Limit) it may detach the queue connecting it to the worker before reading all of the worker's tuples. Rather than let the worker continue to generate and send all of the results, have it stop after sending the next tuple. More could be done here to stop the worker even quicker, but this is about as well as we can hope to do for 9.6. This is in response to a problem report from Andreas Seltenreich. Commit 44339b892a04e94bbb472235882dc6f7023bdc65 should be actually be sufficient to fix that example even without this change, but it seems better to do this, too, since we might otherwise waste quite a large amount of effort in one or more workers. Discussion: CAA4eK1KOKGqmz9bGu+Z42qhRwMbm4R5rfnqsLCNqFs9j14jzEA@mail.gmail.com Amit Kapila
2016-05-27Be more predictable about reporting "lock timeout" vs "statement timeout".Tom Lane
If both timeout indicators are set when we arrive at ProcessInterrupts, we've historically just reported "lock timeout". However, some buildfarm members have been observed to fail isolationtester's timeouts test by reporting "lock timeout" when the statement timeout was expected to fire first. The cause seems to be that the process is allowed to sleep longer than expected (probably due to heavy machine load) so that the lock timeout happens before we reach the point of reporting the error, and then this arbitrary tiebreak rule does the wrong thing. We can improve matters by comparing the scheduled timeout times to decide which error to report. I had originally proposed greatly reducing the 1-second window between the two timeouts in the test cases. On reflection that is a bad idea, at least for the case where the lock timeout is expected to fire first, because that would assume that it takes negligible time to get from statement start to the beginning of the lock wait. Thus, this patch doesn't completely remove the risk of test failures on slow machines. Empirically, however, the case this handles is the one we are seeing in the buildfarm. The explanation may be that the other case requires the scheduler to take the CPU away from a busy process, whereas the case fixed here only requires the scheduler to not give the CPU back right away to a process that has been woken from a multi-second sleep (and, perhaps, has been swapped out meanwhile). Back-patch to 9.3 where the isolationtester timeouts test was added. Discussion: <8693.1464314819@sss.pgh.pa.us>
2016-04-05Support ALTER THING .. DEPENDS ON EXTENSIONAlvaro Herrera
This introduces a new dependency type which marks an object as depending on an extension, such that if the extension is dropped, the object automatically goes away; and also, if the database is dumped, the object is included in the dump output. Currently the grammar supports this for indexes, triggers, materialized views and functions only, although the utility code is generic so adding support for more object types is a matter of touching the parser rules only. Author: Abhijit Menon-Sen Reviewed-by: Alexander Korotkov, Álvaro Herrera Discussion: http://www.postgresql.org/message-id/20160115062649.GA5068@toroid.org
2016-03-23Support CREATE ACCESS METHODAlvaro Herrera
This enables external code to create access methods. This is useful so that extensions can add their own access methods which can be formally tracked for dependencies, so that DROP operates correctly. Also, having explicit support makes pg_dump work correctly. Currently only index AMs are supported, but we expect different types to be added in the future. Authors: Alexander Korotkov, Petr Jelínek Reviewed-By: Teodor Sigaev, Petr Jelínek, Jim Nasby Commitfest-URL: https://commitfest.postgresql.org/9/353/ Discussion: https://www.postgresql.org/message-id/CAPpHfdsXwZmojm6Dx+TJnpYk27kT4o7Ri6X_4OSWcByu1Rm+VA@mail.gmail.com