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* Tweak catalog indexing abstraction for upcoming WARMAlvaro Herrera2017-01-31
| | | | | | | | | | | | | | | | | | | | | Split the existing CatalogUpdateIndexes into two different routines, CatalogTupleInsert and CatalogTupleUpdate, which do both the heap insert/update plus the index update. This removes over 300 lines of boilerplate code all over src/backend/catalog/ and src/backend/commands. The resulting code is much more pleasing to the eye. Also, by encapsulating what happens in detail during an UPDATE, this facilitates the upcoming WARM patch, which is going to add a few more lines to the update case making the boilerplate even more boring. The original CatalogUpdateIndexes is removed; there was only one use left, and since it's just three lines, we can as well expand it in place there. We could keep it, but WARM is going to break all the UPDATE out-of-core callsites anyway, so there seems to be no benefit in doing so. Author: Pavan Deolasee Discussion: https://www.postgr.es/m/CABOikdOcFYSZ4vA2gYfs=M2cdXzXX4qGHeEiW3fu9PCfkHLa2A@mail.gmail.com
* Use castNode() in a bunch of statement-list-related code.Tom Lane2017-01-26
| | | | | | | | | | | | | 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.
* Fix typo: pg_statistics -> pg_statisticPeter Eisentraut2017-01-25
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* Move some things from builtins.h to new header filesPeter Eisentraut2017-01-20
| | | | This avoids that builtins.h has to include additional header files.
* Logical replicationPeter Eisentraut2017-01-20
| | | | | | | | | | | | | - 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>
* Change representation of statement lists, and add statement location info.Tom Lane2017-01-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* Invalidate cached plans on FDW option changes.Tom Lane2017-01-06
| | | | | | | | | | | | | | | | | | | | | | | | This fixes problems where a plan must change but fails to do so, as seen in a bug report from Rajkumar Raghuwanshi. For ALTER FOREIGN TABLE OPTIONS, do this through the standard method of forcing a relcache flush on the table. For ALTER FOREIGN DATA WRAPPER and ALTER SERVER, just flush the whole plan cache on any change in pg_foreign_data_wrapper or pg_foreign_server. That matches the way we handle some other low-probability cases such as opclass changes, and it's unclear that the case arises often enough to be worth working harder. Besides, that gives a patch that is simple enough to back-patch with confidence. Back-patch to 9.3. In principle we could apply the code change to 9.2 as well, but (a) we lack postgres_fdw to test it with, (b) it's doubtful that anyone is doing anything exciting enough with FDWs that far back to need this desperately, and (c) the patch doesn't apply cleanly. Patch originally by Amit Langote, reviewed by Etsuro Fujita and Ashutosh Bapat, who each contributed substantial changes as well. Discussion: https://postgr.es/m/CAKcux6m5cA6rRPTKkqVdJ-R=KKDfe35Q_ZuUqxDSV_4hwga=og@mail.gmail.com
* Update copyright via script for 2017Bruce Momjian2017-01-03
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* Add pg_sequence system catalogPeter Eisentraut2016-12-20
| | | | | | | | | | Move sequence metadata (start, increment, etc.) into a proper system catalog instead of storing it in the sequence heap object. This separates the metadata from the sequence data. Sequence metadata is now operated on transactionally by DDL commands, whereas previously rollbacks of sequence-related DDL commands would be ignored. Reviewed-by: Andreas Karlsson <andreas@proxel.se>
* Implement table partitioning.Robert Haas2016-12-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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.
* Silence compiler warningsStephen Frost2016-12-06
| | | | | | | | | | | | | | | | Rearrange a bit of code to ensure that 'mode' in LWLockRelease is obviously always set, which seems a bit cleaner and avoids a compiler warning (thanks to Robert for the suggestion!). In GetCachedPlan(), initialize 'plan' to silence a compiler warning, but also add an Assert() to make sure we don't ever actually fall through with 'plan' still being set to NULL, since we are about to dereference it. Neither of these appear to be live bugs but at least gcc 5.4.0-6ubuntu1~16.04.4 doesn't quite have the smarts to realize that. Discussion: https://www.postgresql.org/message-id/20161129152102.GR13284%40tamriel.snowman.net
* Simplify code by getting rid of SPI_push, SPI_pop, SPI_restore_connection.Tom Lane2016-11-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The idea behind SPI_push was to allow transitioning back into an "unconnected" state when a SPI-using procedure calls unrelated code that might or might not invoke SPI. That sounds good, but in practice the only thing it does for us is to catch cases where a called SPI-using function forgets to call SPI_connect --- which is a highly improbable failure mode, since it would be exposed immediately by direct testing of said function. As against that, we've had multiple bugs induced by forgetting to call SPI_push/SPI_pop around code that might invoke SPI-using functions; these are much harder to catch and indeed have gone undetected for years in some cases. And we've had to band-aid around some problems of this ilk by introducing conditional push/pop pairs in some places, which really kind of defeats the purpose altogether; if we can't draw bright lines between connected and unconnected code, what's the point? Hence, get rid of SPI_push[_conditional], SPI_pop[_conditional], and the underlying state variable _SPI_curid. It turns out SPI_restore_connection can go away too, which is a nice side benefit since it was never more than a kluge. Provide no-op macros for the deleted functions so as to avoid an API break for external modules. A side effect of this removal is that SPI_palloc and allied functions no longer permit being called when unconnected; they'll throw an error instead. The apparent usefulness of the previous behavior was a mirage as well, because it was depended on by only a few places (which I fixed in preceding commits), and it posed a risk of allocations being unexpectedly long-lived if someone forgot a SPI_push call. Discussion: <20808.1478481403@sss.pgh.pa.us>
* Remove unnecessary int2vector-specific hash function and equality operator.Tom Lane2016-10-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | These functions were originally added in commit d8cedf67a to support use of int2vector columns as catcache lookup keys. However, there are no catcaches that use such columns. (Indeed I now think it must always have been dead code: a catcache with such a key column would need an underlying unique index on the column, but we've never had an int2vector btree opclass.) Getting rid of the int2vector-specific operator and function does not lose any functionality, because operations on int2vectors will now fall back to the generic anyarray support. This avoids a wart that a btree index on an int2vector column (made using anyarray_ops) would fail to match equality searches, because int2vectoreq wasn't a member of the opclass. We don't really care much about that, since int2vector is not meant as a type for users to use, but it's silly to have extra code and less functionality. If we ever do want a catcache to be indexed by an int2vector column, we'd need to put back full btree and hash opclasses for int2vector, comparable to the support for oidvector. (The anyarray code can't be used at such a low level, because it needs to do catcache lookups.) But we'll deal with that if/when the need arises. Also worth noting is that removal of the hash int2vector_ops opclass will break any user-created hash indexes on int2vector columns. While hash anyarray_ops would serve the same purpose, it would probably not compute the same hash values and thus wouldn't be on-disk-compatible. Given that int2vector isn't a user-facing type and we're planning other incompatible changes in hash indexes for v10 anyway, this doesn't seem like something to worry about, but it's probably worth mentioning here. Amit Langote Discussion: <d9bb74f8-b194-7307-9ebd-90645d377e45@lab.ntt.co.jp>
* Avoid reporting "cache lookup failed" for some user-reachable cases.Tom Lane2016-09-09
| | | | | | | | | | | | | | | | | | | | | | We have a not-terribly-thoroughly-enforced-yet project policy that internal errors with SQLSTATE XX000 (ie, plain elog) should not be triggerable from SQL. record_in, domain_in, and PL validator functions all failed to meet this standard, because they threw plain elog("cache lookup failed for XXX") errors on bad OIDs, and those are all invokable from SQL. For record_in, the best fix is to upgrade typcache.c (lookup_type_cache) to throw a user-facing error for this case. That seems consistent because it was more than halfway there already, having user-facing errors for shell types and non-composite types. Having done that, tweak domain_in to rely on the typcache to throw an appropriate error. (This costs little because InitDomainConstraintRef would fetch the typcache entry anyway.) For the PL validator functions, we already have a single choke point at CheckFunctionValidatorAccess, so just fix its error to be user-facing. Dilip Kumar, reviewed by Haribabu Kommi Discussion: <87wpxfygg9.fsf@credativ.de>
* Add macros to make AllocSetContextCreate() calls simpler and safer.Tom Lane2016-08-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* Avoid invalidating all foreign-join cached plans when user mappings change.Tom Lane2016-07-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We must not push down a foreign join when the foreign tables involved should be accessed under different user mappings. Previously we tried to enforce that rule literally during planning, but that meant that the resulting plans were dependent on the current contents of the pg_user_mapping catalog, and we had to blow away all cached plans containing any remote join when anything at all changed in pg_user_mapping. This could have been improved somewhat, but the fact that a syscache inval callback has very limited info about what changed made it hard to do better within that design. Instead, let's change the planner to not consider user mappings per se, but to allow a foreign join if both RTEs have the same checkAsUser value. If they do, then they necessarily will use the same user mapping at runtime, and we don't need to know specifically which one that is. Post-plan-time changes in pg_user_mapping no longer require any plan invalidation. This rule does give up some optimization ability, to wit where two foreign table references come from views with different owners or one's from a view and one's directly in the query, but nonetheless the same user mapping would have applied. We'll sacrifice the first case, but to not regress more than we have to in the second case, allow a foreign join involving both zero and nonzero checkAsUser values if the nonzero one is the same as the prevailing effective userID. In that case, mark the plan as only runnable by that userID. The plancache code already had a notion of plans being userID-specific, in order to support RLS. It was a little confused though, in particular lacking clarity of thought as to whether it was the rewritten query or just the finished plan that's dependent on the userID. Rearrange that code so that it's clearer what depends on which, and so that the same logic applies to both RLS-injected role dependency and foreign-join-injected role dependency. Note that this patch doesn't remove the other issue mentioned in the original complaint, which is that while we'll reliably stop using a foreign join if it's disallowed in a new context, we might fail to start using a foreign join if it's now allowed, but we previously created a generic cached plan that didn't use one. It was agreed that the chance of winning that way was not high enough to justify the much larger number of plan invalidations that would have to occur if we tried to cause it to happen. In passing, clean up randomly-varying spelling of EXPLAIN commands in postgres_fdw.sql, and fix a COSTS ON example that had been allowed to leak into the committed tests. This reverts most of commits fbe5a3fb7 and 5d4171d1c, which were the previous attempt at ensuring we wouldn't push down foreign joins that span permissions contexts. Etsuro Fujita and Tom Lane Discussion: <d49c1e5b-f059-20f4-c132-e9752ee0113e@lab.ntt.co.jp>
* Restore foreign-key-aware estimation of join relation sizes.Tom Lane2016-06-18
| | | | | | | | | | | | | | | | | | | | This patch provides a new implementation of the logic added by commit 137805f89 and later removed by 77ba61080. It differs from the original primarily in expending much less effort per joinrel in large queries, which it accomplishes by doing most of the matching work once per query not once per joinrel. Hopefully, it's also less buggy and better commented. The never-documented enable_fkey_estimates GUC remains gone. There remains work to be done to make the selectivity estimates account for nulls in FK referencing columns; but that was true of the original patch as well. We may be able to address this point later in beta. In the meantime, any error should be in the direction of overestimating rather than underestimating joinrel sizes, which seems like the direction we want to err in. Tomas Vondra and Tom Lane Discussion: <31041.1465069446@sss.pgh.pa.us>
* Refactor to reduce code duplication for function property checking.Tom Lane2016-06-10
| | | | | | | | | | | | | | | | | | | | | | | As noted by Andres Freund, we'd accumulated quite a few similar functions in clauses.c that examine all functions in an expression tree to see if they satisfy some boolean test. Reduce the duplication by inventing a function check_functions_in_node() that applies a simple callback function to each SQL function OID appearing in a given expression node. This also fixes some arguable oversights; for example, contain_mutable_functions() did not check aggregate or window functions for mutability. I doubt that that represents a live bug at the moment, because we don't really consider mutability for aggregates; but it might someday be one. I chose to put check_functions_in_node() in nodeFuncs.c because it seemed like other modules might wish to use it in future. That in turn forced moving set_opfuncid() et al into nodeFuncs.c, as the alternative was for nodeFuncs.c to depend on optimizer/setrefs.c which didn't seem very clean. In passing, teach contain_leaked_vars_walker() about a few more expression node types it can safely look through, and improve the rather messy and undercommented code in has_parallel_hazard_walker(). Discussion: <20160527185853.ziol2os2zskahl7v@alap3.anarazel.de>
* Improve the situation for parallel query versus temp relations.Tom Lane2016-06-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Transmit the leader's temp-namespace state to workers. This is important because without it, the workers do not really have the same search path as the leader. For example, there is no good reason (and no extant code either) to prevent a worker from executing a temp function that the leader created previously; but as things stood it would fail to find the temp function, and then either fail or execute the wrong function entirely. We still prohibit a worker from creating a temp namespace on its own. In effect, a worker can only see the session's temp namespace if the leader had created it before starting the worker, which seems like the right semantics. Also, transmit the leader's BackendId to workers, and arrange for workers to use that when determining the physical file path of a temp relation belonging to their session. While the original intent was to prevent such accesses entirely, there were a number of holes in that, notably in places like dbsize.c which assume they can safely access temp rels of other sessions anyway. We might as well get this right, as a small down payment on someday allowing workers to access the leader's temp tables. (With this change, directly using "MyBackendId" as a relation or buffer backend ID is deprecated; you should use BackendIdForTempRelations() instead. I left a couple of such uses alone though, as they're not going to be reachable in parallel workers until we do something about localbuf.c.) Move the thou-shalt-not-access-thy-leader's-temp-tables prohibition down into localbuf.c, which is where it actually matters, instead of having it in relation_open(). This amounts to recognizing that access to temp tables' catalog entries is perfectly safe in a worker, it's only the data in local buffers that is problematic. Having done all that, we can get rid of the test in has_parallel_hazard() that says that use of a temp table's rowtype is unsafe in parallel workers. That test was unduly expensive, and if we really did need such a prohibition, that was not even close to being a bulletproof guard for it. (For example, any user-defined function executed in a parallel worker might have attempted such access.)
* pgindent run for 9.6Robert Haas2016-06-09
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* Revert "Use Foreign Key relationships to infer multi-column join selectivity".Tom Lane2016-06-07
| | | | | | | | | | | | | | This commit reverts 137805f89 as well as the associated commits 015e88942, 5306df283, and 68d704edb. We found multiple bugs in this feature, and there was concern about possible planner slowdown (though to be fair, exhibiting a very large slowdown proved difficult). The way forward requires a considerable rewrite, which may or may not be possible to accomplish in time for beta2. In my judgment reviewing the rewrite will be easier to accomplish starting from a clean slate, so let's temporarily revert what's there now. This also leaves us in a safe state if it turns out to be necessary to postpone the rewrite to the next development cycle. Discussion: <20160429102531.GA13701@huehner.biz>
* Fix hash index vs "snapshot too old" problemmsKevin Grittner2016-05-06
| | | | | | | | | | | | | | | | Hash indexes are not WAL-logged, and so do not maintain the LSN of index pages. Since the "snapshot too old" feature counts on detecting error conditions using the LSN of a table and all indexes on it, this makes it impossible to safely do early vacuuming on any table with a hash index, so add this to the tests for whether the xid used to vacuum a table can be adjusted based on old_snapshot_threshold. While at it, add a paragraph to the docs for old_snapshot_threshold which specifically mentions this and other aspects of the feature which may otherwise surprise users. Problem reported and patch reviewed by Amit Kapila
* Emit invalidations to standby for transactions without xid.Andres Freund2016-04-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | So far, when a transaction with pending invalidations, but without an assigned xid, committed, we simply ignored those invalidation messages. That's problematic, because those are actually sent for a reason. Known symptoms of this include that existing sessions on a hot-standby replica sometimes fail to notice new concurrently built indexes and visibility map updates. The solution is to WAL log such invalidations in transactions without an xid. We considered to alternatively force-assign an xid, but that'd be problematic for vacuum, which might be run in systems with few xids. Important: This adds a new WAL record, but as the patch has to be back-patched, we can't bump the WAL page magic. This means that standbys have to be updated before primaries; otherwise "PANIC: standby_redo: unknown op code 32" errors can be encountered. XXX: Reported-By: Васильев Дмитрий, Masahiko Sawada Discussion: CAB-SwXY6oH=9twBkXJtgR4UC1NqT-vpYAtxCseME62ADwyK5OA@mail.gmail.com CAD21AoDpZ6Xjg=gFrGPnSn4oTRRcwK1EBrWCq9OqOHuAcMMC=w@mail.gmail.com
* Revert CREATE INDEX ... INCLUDING ...Teodor Sigaev2016-04-08
| | | | | | It's not ready yet, revert two commits 690c543550b0d2852060c18d270cdb534d339d9a - unstable test output 386e3d7609c49505e079c40c65919d99feb82505 - patch itself
* CREATE INDEX ... INCLUDING (column[, ...])Teodor Sigaev2016-04-08
| | | | | | | | | | Now indexes (but only B-tree for now) can contain "extra" column(s) which doesn't participate in index structure, they are just stored in leaf tuples. It allows to use index only scan by using single index instead of two or more indexes. Author: Anastasia Lubennikova with minor editorializing by me Reviewers: David Rowley, Peter Geoghegan, Jeff Janes
* Load FK defs into relcache for use by plannerSimon Riggs2016-04-07
| | | | | | | Fastpath ignores this if no triggers defined. Author: Tomas Vondra, with fastpath and comments added by me Reviewers: David Rowley, Simon Riggs
* Reset plan->row_security_env and planUserIdStephen Frost2016-03-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the plancache, we check if the environment we planned the query under has changed in a way which requires us to re-plan, such as when the user for whom the plan was prepared changes and RLS is being used (and, therefore, there may be different policies to apply). Unfortunately, while those values were set and checked, they were not being reset when the query was re-planned and therefore, in cases where we change role, re-plan, and then change role again, we weren't re-planning again. This leads to potentially incorrect policies being applied in cases where role-specific policies are used and a given query is planned under one role and then executed under other roles, which could happen under security definer functions or when a common user and query is planned initially and then re-used across multiple SET ROLEs. Further, extensions which made use of CopyCachedPlan() may suffer from similar issues as the RLS-related fields were not properly copied as part of the plan and therefore RevalidateCachedQuery() would copy in the current settings without invalidating the query. Fix by using the same approach used for 'search_path', where we set the correct values in CompleteCachedPlan(), check them early on in RevalidateCachedQuery() and then properly reset them if re-planning. Also, copy through the values during CopyCachedPlan(). Pointed out by Ashutosh Bapat. Reviewed by Michael Paquier. Back-patch to 9.5 where RLS was introduced. Security: CVE-2016-2193
* Only try to push down foreign joins if the user mapping OIDs match.Robert Haas2016-01-28
| | | | | | | | | | | | | Previously, the foreign join pushdown infrastructure left the question of security entirely up to individual FDWs, but it would be easy for a foreign data wrapper to inadvertently open up subtle security holes that way. So, make it the core code's job to determine which user mapping OID is relevant, and don't attempt join pushdown unless it's the same for all relevant relations. Per a suggestion from Tom Lane. Shigeru Hanada and Ashutosh Bapat, reviewed by Etsuro Fujita and KaiGai Kohei, with some further changes by me.
* Improve index AMs' opclass validation procedures.Tom Lane2016-01-21
| | | | | | | | | | | | | | | | | | | | The amvalidate functions added in commit 65c5fcd353a859da were on the crude side. Improve them in a few ways: * Perform signature checking for operators and support functions. * Apply more thorough checks for missing operators and functions, where possible. * Instead of reporting problems as ERRORs, report most problems as INFO messages and make the amvalidate function return FALSE. This allows more than one problem to be discovered per run. * Report object names rather than OIDs, and work a bit harder on making the messages understandable. Also, remove a few more opr_sanity regression test queries that are now superseded by the amvalidate checks.
* Restructure index access method API to hide most of it at the C level.Tom Lane2016-01-17
| | | | | | | | | | | | | | | | | | | | | | | | This patch reduces pg_am to just two columns, a name and a handler function. All the data formerly obtained from pg_am is now provided in a C struct returned by the handler function. This is similar to the designs we've adopted for FDWs and tablesample methods. There are multiple advantages. For one, the index AM's support functions are now simple C functions, making them faster to call and much less error-prone, since the C compiler can now check function signatures. For another, this will make it far more practical to define index access methods in installable extensions. A disadvantage is that SQL-level code can no longer see attributes of index AMs; in particular, some of the crosschecks in the opr_sanity regression test are no longer possible from SQL. We've addressed that by adding a facility for the index AM to perform such checks instead. (Much more could be done in that line, but for now we're content if the amvalidate functions more or less replace what opr_sanity used to do.) We might also want to expose some sort of reporting functionality, but this patch doesn't do that. Alexander Korotkov, reviewed by Petr Jelínek, and rather heavily editorialized on by me.
* Make pg_shseclabel available in early backend startupAlvaro Herrera2016-01-05
| | | | | | | | | | | | While the in-core authentication mechanism doesn't need to access pg_shseclabel at all, it's reasonable to think that an authentication hook will want to look at the label for the role logging in, or for rows in other catalogs used during the authentication phase of startup. Catalog version bumped, because this changes the "is nailed" status for pg_shseclabel. Author: Adam Brightwell
* Update copyright for 2016Bruce Momjian2016-01-02
| | | | Backpatch certain files through 9.1
* Avoid caching expression state trees for domain constraints across queries.Tom Lane2015-11-29
| | | | | | | | | | | | | | | | | | | | | | In commit 8abb3cda0ddc00a0ab98977a1633a95b97068d4e I attempted to cache the expression state trees constructed for domain CHECK constraints for the life of the backend (assuming the domain's constraints don't get redefined). However, this turns out not to work very well, because execQual.c will run those state trees with ecxt_per_query_memory pointing to a query-lifespan context, and in some situations we'll end up with pointers into that context getting stored into the state trees. This happens in particular with SQL-language functions, as reported by Emre Hasegeli, but there are many other cases. To fix, keep only the expression plan trees for domain CHECK constraints in the typcache's data structure, and revert to performing ExecInitExpr (at least) once per query to set up expression state trees in the query's context. Eventually it'd be nice to undo this, but that will require some careful thought about memory management for expression state trees, and it seems far too late for any such redesign in 9.5. This way is still much more efficient than what happened before 8abb3cda0.
* Be more noisy about "wrong number of nailed relations" initfile problems.Tom Lane2015-11-11
| | | | | | | | | | | | | | | | | | | | | In commit 5d1ff6bd559ea8df1b7302e245e690b01b9a4fa4 I added some logic to relcache.c to try to ensure that the regression tests would fail if we made a mistake about which relations belong in the relcache init files. I'm quite sure I tested that, but I must have done so only for the non-shared-catalog case, because a report from Adam Brightwell showed that the regression tests still pass just fine if we bollix the shared-catalog init file in the way this code was supposed to catch. The reason is that that file gets loaded before we do client authentication, so the WARNING is not sent to the client, only to the postmaster log, where it's far too easily missed. The least Rube Goldbergian answer to this is to put an Assert(false) after the elog(WARNING). That will certainly get developers' attention, while not breaking production builds' ability to recover from corner cases with similar symptoms. Since this is only of interest to developers, there seems no need for a back-patch, even though the previous commit went into all branches.
* Generate parallel sequential scan plans in simple cases.Robert Haas2015-11-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a new flag, consider_parallel, to each RelOptInfo, indicating whether a plan for that relation could conceivably be run inside of a parallel worker. Right now, we're pretty conservative: for example, it might be possible to defer applying a parallel-restricted qual in a worker, and later do it in the leader, but right now we just don't try to parallelize access to that relation. That's probably the right decision in most cases, anyway. Using the new flag, generate parallel sequential scan plans for plain baserels, meaning that we now have parallel sequential scan in PostgreSQL. The logic here is pretty unsophisticated right now: the costing model probably isn't right in detail, and we can't push joins beneath Gather nodes, so the number of plans that can actually benefit from this is pretty limited right now. Lots more work is needed. Nevertheless, it seems time to enable this functionality so that all this code can actually be tested easily by users and developers. Note that, if you wish to test this functionality, it will be necessary to set max_parallel_degree to a value greater than the default of 0. Once a few more loose ends have been tidied up here, we might want to consider changing the default value of this GUC, but I'm leaving it alone for now. Along the way, fix a bug in cost_gather: the previous coding thought that a Gather node's transfer overhead should be costed on the basis of the relation size rather than the number of tuples that actually need to be passed off to the leader. Patch by me, reviewed in earlier versions by Amit Kapila.
* Remove the SECURITY_ROW_LEVEL_DISABLED security context bit.Noah Misch2015-09-20
| | | | | | | | | | This commit's parent made superfluous the bit's sole usage. Referential integrity checks have long run as the subject table's owner, and that now implies RLS bypass. Safe use of the bit was tricky, requiring strict control over the SQL expressions evaluating therein. Back-patch to 9.5, where the bit was introduced. Based on a patch by Stephen Frost.
* Determine whether it's safe to attempt a parallel plan for a query.Robert Haas2015-09-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 924bcf4f16d54c55310b28f77686608684734f42 introduced a framework for parallel computation in PostgreSQL that makes most but not all built-in functions safe to execute in parallel mode. In order to have parallel query, we'll need to be able to determine whether that query contains functions (either built-in or user-defined) that cannot be safely executed in parallel mode. This requires those functions to be labeled, so this patch introduces an infrastructure for that. Some functions currently labeled as safe may need to be revised depending on how pending issues related to heavyweight locking under paralllelism are resolved. Parallel plans can't be used except for the case where the query will run to completion. If portal execution were suspended, the parallel mode restrictions would need to remain in effect during that time, but that might make other queries fail. Therefore, this patch introduces a framework that enables consideration of parallel plans only when it is known that the plan will be run to completion. This probably needs some refinement; for example, at bind time, we do not know whether a query run via the extended protocol will be execution to completion or run with a limited fetch count. Having the client indicate its intentions at bind time would constitute a wire protocol break. Some contexts in which parallel mode would be safe are not adjusted by this patch; the default is not to try parallel plans except from call sites that have been updated to say that such plans are OK. This commit doesn't introduce any parallel paths or plans; it just provides a way to determine whether they could potentially be used. I'm committing it on the theory that the remaining parallel sequential scan patches will also get committed to this release, hopefully in the not-too-distant future. Robert Haas and Amit Kapila. Reviewed (in earlier versions) by Noah Misch.
* RLS refactoringStephen Frost2015-09-15
| | | | | | | | | | | | | | | | This refactors rewrite/rowsecurity.c to simplify the handling of the default deny case (reducing the number of places where we check for and add the default deny policy from three to one) by splitting up the retrival of the policies from the application of them. This also allowed us to do away with the policy_id field. A policy_name field was added for WithCheckOption policies and is used in error reporting, when available. Patch by Dean Rasheed, with various mostly cosmetic changes by me. Back-patch to 9.5 where RLS was introduced to avoid unnecessary differences, since we're still in alpha, per discussion with Robert.
* Allow per-tablespace effective_io_concurrencyAlvaro Herrera2015-09-08
| | | | | | | | | | Per discussion, nowadays it is possible to have tablespaces that have wildly different I/O characteristics from others. Setting different effective_io_concurrency parameters for those has been measured to improve performance. Author: Julien Rouhaud Reviewed by: Andres Freund
* Fix subtransaction cleanup after an outer-subtransaction portal fails.Tom Lane2015-09-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Formerly, we treated only portals created in the current subtransaction as having failed during subtransaction abort. However, if the error occurred while running a portal created in an outer subtransaction (ie, a cursor declared before the last savepoint), that has to be considered broken too. To allow reliable detection of which ones those are, add a bookkeeping field to struct Portal that tracks the innermost subtransaction in which each portal has actually been executed. (Without this, we'd end up failing portals containing functions that had called the subtransaction, thereby breaking plpgsql exception blocks completely.) In addition, when we fail an outer-subtransaction Portal, transfer its resources into the subtransaction's resource owner, so that they're released early in cleanup of the subxact. This fixes a problem reported by Jim Nasby in which a function executed in an outer-subtransaction cursor could cause an Assert failure or crash by referencing a relation created within the inner subtransaction. The proximate cause of the Assert failure is that AtEOSubXact_RelationCache assumed it could blow away a relcache entry without first checking that the entry had zero refcount. That was a bad idea on its own terms, so add such a check there, and to the similar coding in AtEOXact_RelationCache. This provides an independent safety measure in case there are still ways to provoke the situation despite the Portal-level changes. This has been broken since subtransactions were invented, so back-patch to all supported branches. Tom Lane and Michael Paquier
* Plug RLS related information leak in pg_stats view.Joe Conway2015-07-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The pg_stats view is supposed to be restricted to only show rows about tables the user can read. However, it sometimes can leak information which could not otherwise be seen when row level security is enabled. Fix that by not showing pg_stats rows to users that would be subject to RLS on the table the row is related to. This is done by creating/using the newly introduced SQL visible function, row_security_active(). Along the way, clean up three call sites of check_enable_rls(). The second argument of that function should only be specified as other than InvalidOid when we are checking as a different user than the current one, as in when querying through a view. These sites were passing GetUserId() instead of InvalidOid, which can cause the function to return incorrect results if the current user has the BYPASSRLS privilege and row_security has been set to OFF. Additionally fix a bug causing RI Trigger error messages to unintentionally leak information when RLS is enabled, and other minor cleanup and improvements. Also add WITH (security_barrier) to the definition of pg_stats. Bumped CATVERSION due to new SQL functions and pg_stats view definition. Back-patch to 9.5 where RLS was introduced. Reported by Yaroslav. Patch by Joe Conway and Dean Rasheed with review and input by Michael Paquier and Stephen Frost.
* Redesign tablesample method API, and do extensive code review.Tom Lane2015-07-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | The original implementation of TABLESAMPLE modeled the tablesample method API on index access methods, which wasn't a good choice because, without specialized DDL commands, there's no way to build an extension that can implement a TSM. (Raw inserts into system catalogs are not an acceptable thing to do, because we can't undo them during DROP EXTENSION, nor will pg_upgrade behave sanely.) Instead adopt an API more like procedural language handlers or foreign data wrappers, wherein the only SQL-level support object needed is a single handler function identified by having a special return type. This lets us get rid of the supporting catalog altogether, so that no custom DDL support is needed for the feature. Adjust the API so that it can support non-constant tablesample arguments (the original coding assumed we could evaluate the argument expressions at ExecInitSampleScan time, which is undesirable even if it weren't outright unsafe), and discourage sampling methods from looking at invisible tuples. Make sure that the BERNOULLI and SYSTEM methods are genuinely repeatable within and across queries, as required by the SQL standard, and deal more honestly with methods that can't support that requirement. Make a full code-review pass over the tablesample additions, and fix assorted bugs, omissions, infelicities, and cosmetic issues (such as failure to put the added code stanzas in a consistent ordering). Improve EXPLAIN's output of tablesample plans, too. Back-patch to 9.5 so that we don't have to support the original API in production.
* Fix the logic for putting relations into the relcache init file.Tom Lane2015-06-25
| | | | | | | | | | | | | | | | | | | | | | | | | | Commit f3b5565dd4e59576be4c772da364704863e6a835 was a couple of bricks shy of a load; specifically, it missed putting pg_trigger_tgrelid_tgname_index into the relcache init file, because that index is not used by any syscache. However, we have historically nailed that index into cache for performance reasons. The upshot was that load_relcache_init_file always decided that the init file was busted and silently ignored it, resulting in a significant hit to backend startup speed. To fix, reinstantiate RelationIdIsInInitFile() as a wrapper around RelationSupportsSysCache(), which can know about additional relations that should be in the init file despite being unknown to syscache.c. Also install some guards against future mistakes of this type: make write_relcache_init_file Assert that all nailed relations get written to the init file, and make load_relcache_init_file emit a WARNING if it takes the "wrong number of nailed relations" exit path. Now that we remove the init files during postmaster startup, that case should never occur in the field, even if we are starting a minor-version update that added or removed rels from the nailed set. So the warning shouldn't ever be seen by end users, but it will show up in the regression tests if somebody breaks this logic. Back-patch to all supported branches, like the previous commit.
* Use a safer method for determining whether relcache init file is stale.Tom Lane2015-06-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When we invalidate the relcache entry for a system catalog or index, we must also delete the relcache "init file" if the init file contains a copy of that rel's entry. The old way of doing this relied on a specially maintained list of the OIDs of relations present in the init file: we made the list either when reading the file in, or when writing the file out. The problem is that when writing the file out, we included only rels present in our local relcache, which might have already suffered some deletions due to relcache inval events. In such cases we correctly decided not to overwrite the real init file with incomplete data --- but we still used the incomplete initFileRelationIds list for the rest of the current session. This could result in wrong decisions about whether the session's own actions require deletion of the init file, potentially allowing an init file created by some other concurrent session to be left around even though it's been made stale. Since we don't support changing the schema of a system catalog at runtime, the only likely scenario in which this would cause a problem in the field involves a "vacuum full" on a catalog concurrently with other activity, and even then it's far from easy to provoke. Remarkably, this has been broken since 2002 (in commit 786340441706ac1957a031f11ad1c2e5b6e18314), but we had never seen a reproducible test case until recently. If it did happen in the field, the symptoms would probably involve unexpected "cache lookup failed" errors to begin with, then "could not open file" failures after the next checkpoint, as all accesses to the affected catalog stopped working. Recovery would require manually removing the stale "pg_internal.init" file. To fix, get rid of the initFileRelationIds list, and instead consult syscache.c's list of relations used in catalog caches to decide whether a relation is included in the init file. This should be a tad more efficient anyway, since we're replacing linear search of a list with ~100 entries with a binary search. It's a bit ugly that the init file contents are now so directly tied to the catalog caches, but in practice that won't make much difference. Back-patch to all supported branches.
* pgindent run for 9.5Bruce Momjian2015-05-23
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* Collection of typo fixes.Heikki Linnakangas2015-05-20
| | | | | | | | | | | | | | | Use "a" and "an" correctly, mostly in comments. Two error messages were also fixed (they were just elogs, so no translation work required). Two function comments in pg_proc.h were also fixed. Etsuro Fujita reported one of these, but I found a lot more with grep. Also fix a few other typos spotted while grepping for the a/an typos. For example, "consists out of ..." -> "consists of ...". Plus a "though"/ "through" mixup reported by Euler Taveira. Many of these typos were in old code, which would be nice to backpatch to make future backpatching easier. But much of the code was new, and I didn't feel like crafting separate patches for each branch. So no backpatching.
* TABLESAMPLE, SQL Standard and extensibleSimon Riggs2015-05-15
| | | | | | | | | | | | | | Add a TABLESAMPLE clause to SELECT statements that allows user to specify random BERNOULLI sampling or block level SYSTEM sampling. Implementation allows for extensible sampling functions to be written, using a standard API. Basic version follows SQLStandard exactly. Usable concrete use cases for the sampling API follow in later commits. Petr Jelinek Reviewed by Michael Paquier and Simon Riggs
* Add new OID alias type regnamespaceAndrew Dunstan2015-05-09
| | | | | | Catalog version bumped Kyotaro HORIGUCHI
* Add new OID alias type regroleAndrew Dunstan2015-05-09
| | | | | | | | | | | | | | The new type has the scope of whole the database cluster so it doesn't behave the same as the existing OID alias types which have database scope, concerning object dependency. To avoid confusion constants of the new type are prohibited from appearing where dependencies are made involving it. Also, add a note to the docs about possible MVCC violation and optimization issues, which are general over the all reg* types. Kyotaro Horiguchi
* Introduce replication progress tracking infrastructure.Andres Freund2015-04-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When implementing a replication solution ontop of logical decoding, two related problems exist: * How to safely keep track of replication progress * How to change replication behavior, based on the origin of a row; e.g. to avoid loops in bi-directional replication setups The solution to these problems, as implemented here, consist out of three parts: 1) 'replication origins', which identify nodes in a replication setup. 2) 'replication progress tracking', which remembers, for each replication origin, how far replay has progressed in a efficient and crash safe manner. 3) The ability to filter out changes performed on the behest of a replication origin during logical decoding; this allows complex replication topologies. E.g. by filtering all replayed changes out. Most of this could also be implemented in "userspace", e.g. by inserting additional rows contain origin information, but that ends up being much less efficient and more complicated. We don't want to require various replication solutions to reimplement logic for this independently. The infrastructure is intended to be generic enough to be reusable. This infrastructure also replaces the 'nodeid' infrastructure of commit timestamps. It is intended to provide all the former capabilities, except that there's only 2^16 different origins; but now they integrate with logical decoding. Additionally more functionality is accessible via SQL. Since the commit timestamp infrastructure has also been introduced in 9.5 (commit 73c986add) changing the API is not a problem. For now the number of origins for which the replication progress can be tracked simultaneously is determined by the max_replication_slots GUC. That GUC is not a perfect match to configure this, but there doesn't seem to be sufficient reason to introduce a separate new one. Bumps both catversion and wal page magic. Author: Andres Freund, with contributions from Petr Jelinek and Craig Ringer Reviewed-By: Heikki Linnakangas, Petr Jelinek, Robert Haas, Steve Singer Discussion: 20150216002155.GI15326@awork2.anarazel.de, 20140923182422.GA15776@alap3.anarazel.de, 20131114172632.GE7522@alap2.anarazel.de