aboutsummaryrefslogtreecommitdiff
path: root/src/backend
Commit message (Collapse)AuthorAge
...
* Fix checkpointer crash in EXEC_BACKEND builds.Robert Haas2014-07-24
| | | | | | | | | | | | | | Nothing in the checkpointer calls InitXLOGAccess(), so WALInsertLocks never got initialized there. Without EXEC_BACKEND, it works anyway because the correct value is inherited from the postmaster, but with EXEC_BACKEND we've got a problem. The problem appears to have been introduced by commit 68a2e52bbaf98f136a96b3a0d734ca52ca440a95. To fix, move the relevant initialization steps from InitXLOGAccess() to XLOGShmemInit(), making this more parallel to what we do elsewhere. Amit Kapila
* Properly remove ephemeral replication slots after a crash restart.Andres Freund2014-07-24
| | | | | | | | | | | | Ephemeral slots - slots that shouldn't survive database restarts - weren't properly cleaned up after a immediate/crash restart. They were ignored in the sense that they weren't restored into memory and thus didn't cause unwanted resource retention; but they prevented a new slot with the same name from being created. Now ephemeral slots are fully removed during startup. Backpatch to 9.4 where replication slots where added.
* Avoid access to already-released lock in LockRefindAndRelease.Robert Haas2014-07-24
| | | | Spotted by Tom Lane.
* Re-enable error for "SELECT ... OFFSET -1".Tom Lane2014-07-22
| | | | | | | | | | | The executor has thrown errors for negative OFFSET values since 8.4 (see commit bfce56eea45b1369b7bb2150a150d1ac109f5073), but in a moment of brain fade I taught the planner that OFFSET with a constant negative value was a no-op (commit 1a1832eb085e5bca198735e5d0e766a3cb61b8fc). Reinstate the former behavior by only discarding OFFSET with a value of exactly 0. In passing, adjust a planner comment that referenced the ancient behavior. Back-patch to 9.3 where the mistake was introduced.
* Check block number against the correct fork in get_raw_page().Tom Lane2014-07-22
| | | | | | | | | | | | | | | | | | get_raw_page tried to validate the supplied block number against RelationGetNumberOfBlocks(), which of course is only right when accessing the main fork. In most cases, the main fork is longer than the others, so that the check was too weak (allowing a lower-level error to be reported, but no real harm to be done). However, very small tables could have an FSM larger than their heap, in which case the mistake prevented access to some FSM pages. Per report from Torsten Foertsch. In passing, make the bad-block-number error into an ereport not elog (since it's certainly not an internal error); and fix sloppily maintained comment for RelationGetNumberOfBlocksInFork. This has been wrong since we invented relation forks, so back-patch to all supported branches.
* Allow empty string object keys in json_object().Andrew Dunstan2014-07-22
| | | | | This makes the behaviour consistent with the json parser, other json-generating functions, and the JSON standards.
* Reject out-of-range numeric timezone specifications.Tom Lane2014-07-21
| | | | | | | | | | | | | | | In commit 631dc390f49909a5c8ebd6002cfb2bcee5415a9d, we started to handle simple numeric timezone offsets via the zic library instead of the old CTimeZone/HasCTZSet kluge. However, we overlooked the fact that the zic code will reject UTC offsets exceeding a week (which seems a bit arbitrary, but not because it's too tight ...). This led to possibly setting session_timezone to NULL, which results in crashes in most timezone-related operations as of 9.4, and crashes in a small number of places even before that. So check for NULL return from pg_tzset_offset() and report an appropriate error message. Per bug #11014 from Duncan Gillis. Back-patch to all supported branches, like the previous patch. (Unfortunately, as of today that no longer includes 8.4.)
* Adjust cutoff points in newly-added sanity tests.Tom Lane2014-07-21
| | | | Per recommendation from Andres.
* Defend against bad relfrozenxid/relminmxid/datfrozenxid/datminmxid values.Tom Lane2014-07-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In commit a61daa14d56867e90dc011bbba52ef771cea6770, we fixed pg_upgrade so that it would install sane relminmxid and datminmxid values, but that does not cure the problem for installations that were already pg_upgraded to 9.3; they'll initially have "1" in those fields. This is not a big problem so long as 1 is "in the past" compared to the current nextMultiXact counter. But if an installation were more than halfway to the MXID wrap point at the time of upgrade, 1 would appear to be "in the future" and that would effectively disable tracking of oldest MXIDs in those tables/databases, until such time as the counter wrapped around. While in itself this isn't worse than the situation pre-9.3, where we did not manage MXID wraparound risk at all, the consequences of premature truncation of pg_multixact are worse now; so we ought to make some effort to cope with this. We discussed advising users to fix the tracking values manually, but that seems both very tedious and very error-prone. Instead, this patch adopts two amelioration rules. First, a relminmxid value that is "in the future" is allowed to be overwritten with a full-table VACUUM's actual freeze cutoff, ignoring the normal rule that relminmxid should never go backwards. (This essentially assumes that we have enough defenses in place that wraparound can never occur anymore, and thus that a value "in the future" must be corrupt.) Second, if we see any "in the future" values then we refrain from truncating pg_clog and pg_multixact. This prevents loss of clog data until we have cleaned up all the broken tracking data. In the worst case that could result in considerable clog bloat, but in practice we expect that relfrozenxid-driven freezing will happen soon enough to fix the problem before clog bloat becomes intolerable. (Users could do manual VACUUM FREEZEs if not.) Note that this mechanism cannot save us if there are already-wrapped or already-truncated-away MXIDs in the table; it's only capable of dealing with corrupt tracking values. But that's the situation we have with the pg_upgrade bug. For consistency, apply the same rules to relfrozenxid/datfrozenxid. There are not known mechanisms for these to get messed up, but if they were, the same tactics seem appropriate for fixing them.
* Translation updatesPeter Eisentraut2014-07-21
|
* Update SQL features listPeter Eisentraut2014-07-21
|
* Partial fix for dropped columns in functions returning composite.Tom Lane2014-07-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a view has a function-returning-composite in FROM, and there are some dropped columns in the underlying composite type, ruleutils.c printed junk in the column alias list for the reconstructed FROM entry. Before 9.3, this was prevented by doing get_rte_attribute_is_dropped tests while printing the column alias list; but that solution is not currently available to us for reasons I'll explain below. Instead, check for empty-string entries in the alias list, which can only exist if that column position had been dropped at the time the view was made. (The parser fills in empty strings to preserve the invariant that the aliases correspond to physical column positions.) While this is sufficient to handle the case of columns dropped before the view was made, we have still got issues with columns dropped after the view was made. In particular, the view could contain Vars that explicitly reference such columns! The dependency machinery really ought to refuse the column drop attempt in such cases, as it would do when trying to drop a table column that's explicitly referenced in views. However, we currently neglect to store dependencies on columns of composite types, and fixing that is likely to be too big to be back-patchable (not to mention that existing views in existing databases would not have the needed pg_depend entries anyway). So I'll leave that for a separate patch. Pre-9.3, ruleutils would print such Vars normally (with their original column names) even though it suppressed their entries in the RTE's column alias list. This is certainly bogus, since the printed view definition would fail to reload, but at least it didn't crash. However, as of 9.3 the printed column alias list is tightly tied to the names printed for Vars; so we can't treat columns as dropped for one purpose and not dropped for the other. This is why we can't just put back the get_rte_attribute_is_dropped test: it results in an assertion failure if the view in fact contains any Vars referencing the dropped column. Once we've got dependencies preventing such cases, we'll probably want to do it that way instead of relying on the empty-string test used here. This fix turned up a very ancient bug in outfuncs/readfuncs, namely that T_String nodes containing empty strings were not dumped/reloaded correctly: the node was printed as "<>" which is read as a string value of <>. Since (per SQL) we disallow empty-string identifiers, such nodes don't occur normally, which is why we'd not noticed. (Such nodes aren't used for literal constants, just identifiers.) Per report from Marc Schablewski. Back-patch to 9.3 which is where the rule printing behavior changed. The dangling-variable case is broken all the way back, but that's not what his complaint is about.
* Fix two low-probability memory leaks in regular expression parsing.Tom Lane2014-07-18
| | | | | | | | | | | | | | | | | If pg_regcomp failed after having invoked markst/cleanst, it would leak any "struct subre" nodes it had created. (We've already detected all regex syntax errors at that point, so the only likely causes of later failure would be query cancel or out-of-memory.) To fix, make sure freesrnode knows the difference between the pre-cleanst and post-cleanst cleanup procedures. Add some documentation of this less-than-obvious point. Also, newlacon did the wrong thing with an out-of-memory failure from realloc(), so that the previously allocated array would be leaked. Both of these are pretty low-probability scenarios, but a bug is a bug, so patch all the way back. Per bug #10976 from Arthur O'Dwyer.
* Add option to pg_ctl to choose event source for loggingMagnus Hagander2014-07-17
| | | | | | | | | | | pg_ctl will log to the Windows event log when it is running as a service, which is the primary way of running PostgreSQL on Windows. This option makes it possible to specify which event source to use for this, in order to separate different instances. The server logging itself is still controlled by the regular logging parameters, including a separate setting for the event source. The parameter to pg_ctl only controlls the logging from pg_ctl itself. MauMau, review in many iterations by Amit Kapila and me.
* Fix bugs in SP-GiST search with range type's -|- (adjacent) operator.Heikki Linnakangas2014-07-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The consistent function contained several bugs: * The "if (which2) { ... }" block was broken. It compared the argument's lower bound against centroid's upper bound, while it was supposed to compare the argument's upper bound against the centroid's lower bound (the comment was correct, code was wrong). Also, it cleared bits in the "which1" variable, while it was supposed to clear bits in "which2". * If the argument's upper bound was equal to the centroid's lower bound, we descended to both halves (= all quadrants). That's unnecessary, searching the right quadrants is sufficient. This didn't lead to incorrect query results, but was clearly wrong, and slowed down queries unnecessarily. * In the case that argument's lower bound is adjacent to the centroid's upper bound, we also don't need to visit all quadrants. Per similar reasoning as previous point. * The code where we compare the previous centroid with the current centroid should match the code where we compare the current centroid with the argument. The point of that code is to redo the calculation done in the previous level, to see if we were supposed to traverse left or right (or up or down), and if we actually did. If we moved in the different direction, then we know there are no matches for bound. Refactor the code and adds comments to make it more readable and easier to reason about. Backpatch to 9.3 where SP-GiST support for range types was introduced.
* Allow join removal in some cases involving a left join to a subquery.Tom Lane2014-07-15
| | | | | | | | | | | | | | | | | | | We can remove a left join to a relation if the relation's output is provably distinct for the columns involved in the join clause (considering only equijoin clauses) and the relation supplies no variables needed above the join. Previously, the join removal logic could only prove distinctness by reference to unique indexes of a table. This patch extends the logic to consider subquery relations, wherein distinctness might be proven by reference to GROUP BY, DISTINCT, etc. We actually already had some code to check that a subquery's output was provably distinct, but it was hidden inside pathnode.c; which was a pretty bad place for it really, since that file is mostly boilerplate Path construction and comparison. Move that code to analyzejoins.c, which is arguably a more appropriate location, and is certainly the site of the new usage for it. David Rowley, reviewed by Simon Riggs
* Fix REASSIGN OWNED for text search objectsAlvaro Herrera2014-07-15
| | | | | | | | | | | | | | | | | | | | | Trying to reassign objects owned by a user that had text search dictionaries or configurations used to fail with: ERROR: unexpected classid 3600 or ERROR: unexpected classid 3602 Fix by adding cases for those object types in a switch in pg_shdepend.c. Both REASSIGN OWNED and text search objects go back all the way to 8.1, so backpatch to all supported branches. In 9.3 the alter-owner code was made generic, so the required change in recent branches is pretty simple; however, for 9.2 and older ones we need some additional reshuffling to enable specifying objects by OID rather than name. Text search templates and parsers are not owned objects, so there's no change required for them. Per bug #9749 reported by Michal Novotný
* Include SSL compression status in psql banner and connection loggingMagnus Hagander2014-07-15
| | | | | | Both the psql banner and the connection logging already included SSL status, cipher and bitlength, this adds the information about compression being on or off.
* Small spelling fixPeter Eisentraut2014-07-15
|
* Add missing serial commasPeter Eisentraut2014-07-15
| | | | | Also update one place where the wal_level "logical" was not added to an error message.
* Move view reloptions into their own varlena structAlvaro Herrera2014-07-14
| | | | | | | Per discussion after a gripe from me in http://www.postgresql.org/message-id/20140611194633.GH18688@eldon.alvh.no-ip.org Jaime Casanova
* Add file version information to most installed Windows binaries.Noah Misch2014-07-14
| | | | | | | | Prominent binaries already had this metadata. A handful of minor binaries, such as pg_regress.exe, still lack it; efforts to eliminate such exceptions are welcome. Michael Paquier, reviewed by MauMau.
* Prevent bitmap heap scans from showing unnecessary block info in EXPLAIN ↵Fujii Masao2014-07-14
| | | | | | | | | | | | | | ANALYZE. EXPLAIN ANALYZE shows the information of the numbers of exact/lossy blocks which bitmap heap scan processes. But, previously, when those numbers were both zero, it displayed only the prefix "Heap Blocks:" in TEXT output format. This is strange and would confuse the users. So this commit suppresses such unnecessary information. Backpatch to 9.4 where EXPLAIN ANALYZE was changed so that such information was displayed. Etsuro Fujita
* Fix decoding of consecutive MULTI_INSERTs emitted by one heap_multi_insert().Andres Freund2014-07-12
| | | | | | | | | | | | | | | | | | | Commit 1b86c81d2d fixed the decoding of toasted columns for the rows contained in one xl_heap_multi_insert record. But that's not actually enough, because heap_multi_insert() will actually first toast all passed in rows and then emit several *_multi_insert records; one for each page it fills with tuples. Add a XLOG_HEAP_LAST_MULTI_INSERT flag which is set in xl_heap_multi_insert->flag denoting that this multi_insert record is the last emitted by one heap_multi_insert() call. Then use that flag in decode.c to only set clear_toast_afterwards in the right situation. Expand the number of rows inserted via COPY in the corresponding regression test to make sure that more than one heap page is filled with tuples by one heap_multi_insert() call. Backpatch to 9.4 like the previous commit.
* Fix bug with whole-row references to append subplans.Tom Lane2014-07-11
| | | | | | | | | | | | | | ExecEvalWholeRowVar incorrectly supposed that it could "bless" the source TupleTableSlot just once per query. But if the input is coming from an Append (or, perhaps, other cases?) more than one slot might be returned over the query run. This led to "record type has not been registered" errors when a composite datum was extracted from a non-blessed slot. This bug has been there a long time; I guess it escaped notice because when dealing with subqueries the planner tends to expand whole-row Vars into RowExprs, which don't have the same problem. It is possible to trigger the problem in all active branches, though, as illustrated by the added regression test.
* Fix whitespacePeter Eisentraut2014-07-11
|
* Implement IMPORT FOREIGN SCHEMA.Tom Lane2014-07-10
| | | | | | | | | | | This command provides an automated way to create foreign table definitions that match remote tables, thereby reducing tedium and chances for error. In this patch, we provide the necessary core-server infrastructure and implement the feature fully in the postgres_fdw foreign-data wrapper. Other wrappers will throw a "feature not supported" error until/unless they are updated. Ronan Dunklau and Michael Paquier, additional work by me
* Adjust blank lines around PG_MODULE_MAGIC defines, for consistencyBruce Momjian2014-07-10
| | | | Report by Robert Haas
* Fix error hint style.Robert Haas2014-07-09
| | | | Mistake caught by Tom Lane.
* Improve error messages for bytea decoding failures.Robert Haas2014-07-09
| | | | Craig Ringer
* Don't assume a subquery's output is unique if there's a SRF in its tlist.Tom Lane2014-07-08
| | | | | | | | | | | | | While the x output of "select x from t group by x" can be presumed unique, this does not hold for "select x, generate_series(1,10) from t group by x", because we may expand the set-returning function after the grouping step. (Perhaps that should be re-thought; but considering all the other oddities involved with SRFs in targetlists, it seems unlikely we'll change it.) Put a check in query_is_distinct_for() so it's not fooled by such cases. Back-patch to all supported branches. David Rowley
* Fix typos in comments.Fujii Masao2014-07-07
|
* Fix decoding of MULTI_INSERTs when rows other than the last are toasted.Andres Freund2014-07-06
| | | | | | | | | | | | | | | | | | | | | | | When decoding the results of a HEAP2_MULTI_INSERT (currently only generated by COPY FROM) toast columns for all but the last tuple weren't replaced by their actual contents before being handed to the output plugin. The reassembled toast datums where disregarded after every REORDER_BUFFER_CHANGE_(INSERT|UPDATE|DELETE) which is correct for plain inserts, updates, deletes, but not multi inserts - there we generate several REORDER_BUFFER_CHANGE_INSERTs for a single xl_heap_multi_insert record. To solve the problem add a clear_toast_afterwards boolean to ReorderBufferChange's union member that's used by modifications. All row changes but multi_inserts always set that to true, but multi_insert sets it only for the last change generated. Add a regression test covering decoding of multi_inserts - there was none at all before. Backpatch to 9.4 where logical decoding was introduced. Bug found by Petr Jelinek.
* Consistently pass an "unsigned char" to ctype.h functions.Noah Misch2014-07-06
| | | | | | The isxdigit() calls relied on undefined behavior. The isascii() call was well-defined, but our prevailing style is to include the cast. Back-patch to 9.4, where the isxdigit() calls were introduced.
* Don't cache per-group context across the whole query in orderedsetaggs.c.Tom Lane2014-07-03
| | | | | | | | | | | Although nodeAgg.c currently uses the same per-group memory context for all groups of a query, that might change in future. Avoid assuming it. This costs us an extra AggCheckCallContext() call per group, but that's pretty cheap and is probably good from a safety standpoint anyway. Back-patch to 9.4 in case any third-party code copies this logic. Andrew Gierth
* Redesign API presented by nodeAgg.c for ordered-set and similar aggregates.Tom Lane2014-07-03
| | | | | | | | | | | | | The previous design exposed the input and output ExprContexts of the Agg plan node, but work on grouping sets has suggested that we'll regret doing that. Instead provide more narrowly-defined APIs that can be implemented in multiple ways, namely a way to get a short-term memory context and a way to register an aggregate shutdown callback. Back-patch to 9.4 where the bad APIs were introduced, since we don't want third-party code using these APIs and then having to change in 9.5. Andrew Gierth
* Smooth reporting of commit/rollback statistics.Kevin Grittner2014-07-02
| | | | | | | | | | | | | | | | | | | | If a connection committed or rolled back any transactions within a PGSTAT_STAT_INTERVAL pacing interval without accessing any tables, the reporting of those statistics would be held up until the connection closed or until it ended a PGSTAT_STAT_INTERVAL interval in which it had accessed a table. This could result in under- reporting of transactions for an extended period, followed by a spike in reported transactions. While this is arguably a bug, the impact is minimal, primarily affecting, and being affected by, monitoring software. It might cause more confusion than benefit to change the existing behavior in released stable branches, so apply only to master and the 9.4 beta. Gurjeet Singh, with review and editing by Kevin Grittner, incorporating suggested changes from Abhijit Menon-Sen and Tom Lane.
* Rename logical decoding's pg_llog directory to pg_logical.Andres Freund2014-07-02
| | | | | | | | | | | | | | | The old name wasn't very descriptive as of actual contents of the directory, which are historical snapshots in the snapshots/ subdirectory and mappingdata for rewritten tuples in mappings/. There's been a fair amount of discussion what would be a good name. I'm settling for pg_logical because it's likely that further data around logical decoding and replication will need saving in the future. Also add the missing entry for the directory into storage.sgml's list of PGDATA contents. Bumps catversion as the data directories won't be compatible.
* Add some errdetail to checkRuleResultList().Tom Lane2014-07-02
| | | | | | | | | | | | | | | | | This function wasn't originally thought to be really user-facing, because converting a table to a view isn't something we expect people to do manually. So not all that much effort was spent on the error messages; in particular, while the code will complain that you got the column types wrong it won't say exactly what they are. But since we repurposed the code to also check compatibility of rule RETURNING lists, it's definitely user-facing. It now seems worthwhile to add errdetail messages showing exactly what the conflict is when there's a mismatch of column names or types. This is prompted by bug #10836 from Matthias Raffelsieper, which might have been forestalled if the error message had reported the wrong column type as being "record". Back-patch to 9.4, but not into older branches where the set of translatable error strings is supposed to be stable.
* Allow CREATE/ALTER DATABASE to manipulate datistemplate and datallowconn.Tom Lane2014-07-01
| | | | | | | | | | | Historically these database properties could be manipulated only by manually updating pg_database, which is error-prone and only possible for superusers. But there seems no good reason not to allow database owners to set them for their databases, so invent CREATE/ALTER DATABASE options to do that. Adjust a couple of places that were doing it the hard way to use the commands instead. Vik Fearing, reviewed by Pavel Stehule
* Refactor CREATE/ALTER DATABASE syntax so options need not be keywords.Tom Lane2014-07-01
| | | | | | | | | | | | | Most of the existing option names are keywords anyway, but we can get rid of LC_COLLATE and LC_CTYPE as keywords known to the lexer/grammar. This immediately reduces the size of the grammar tables by about 8KB, and will save more when we add additional CREATE/ALTER DATABASE options in future. A side effect of the implementation is that the CONNECTION LIMIT option can now also be spelled CONNECTION_LIMIT. We choose not to document this, however. Vik Fearing, based on a suggestion by me; reviewed by Pavel Stehule
* Avoid copying index tuples when building an index.Robert Haas2014-07-01
| | | | | | | | | | | | The previous code, perhaps out of concern for avoid memory leaks, formed the tuple in one memory context and then copied it to another memory context. However, this doesn't appear to be necessary, since index_form_tuple and the functions it calls take precautions against leaking memory. In my testing, building the tuple directly inside the sort context shaves several percent off the index build time. Rearrange things so we do that. Patch by me. Review by Amit Kapila, Tom Lane, Andres Freund.
* Check interrupts during logical decoding more frequently.Andres Freund2014-06-30
| | | | | | | | | | | | | | | When reading large amounts of preexisting WAL during logical decoding using the SQL interface we possibly could fail to check interrupts in due time. Similarly the same could happen on systems with a very high WAL volume while creating a new logical replication slot, independent of the used interface. Previously these checks where only performed in xlogreader's read_page callbacks, while waiting for new WAL to be produced. That's not sufficient though, if there's never a need to wait. Walsender's send loop already contains a interrupt check. Backpatch to 9.4 where the logical decoding feature was introduced.
* Fix and enhance the assertion of no palloc's in a critical section.Heikki Linnakangas2014-06-30
| | | | | | | | | | | | The assertion failed if WAL_DEBUG or LWLOCK_STATS was enabled; fix that by using separate memory contexts for the allocations made within those code blocks. This patch introduces a mechanism for marking any memory context as allowed in a critical section. Previously ErrorContext was exempt as a special case. Instead of a blanket exception of the checkpointer process, only exempt the memory context used for the pending ops hash table.
* Remove use_json_as_text options from json_to_record/json_populate_record.Tom Lane2014-06-29
| | | | | | | | | | | | | | | | The "false" case was really quite useless since all it did was to throw an error; a definition not helped in the least by making it the default. Instead let's just have the "true" case, which emits nested objects and arrays in JSON syntax. We might later want to provide the ability to emit sub-objects in Postgres record or array syntax, but we'd be best off to drive that off a check of the target field datatype, not a separate argument. For the functions newly added in 9.4, we can just remove the flag arguments outright. We can't do that for json_populate_record[set], which already existed in 9.3, but we can ignore the argument and always behave as if it were "true". It helps that the flag arguments were optional and not documented in any useful fashion anyway.
* Add cluster_name GUC which is included in process titles if set.Andres Freund2014-06-29
| | | | | | | | | | | | | | | | | | When running several postgres clusters on one OS instance it's often inconveniently hard to identify which "postgres" process belongs to which postgres instance. Add the cluster_name GUC, whose value will be included as part of the process titles if set. With that processes can more easily identified using tools like 'ps'. To avoid problems with encoding mismatches between postgresql.conf, consoles, and individual databases replace non-ASCII chars in the name with question marks. The length is limited to NAMEDATALEN to make it less likely to truncate important information at the end of the status. Thomas Munro, with some adjustments by me and review by a host of people.
* Remove Alpha and Tru64 support.Andres Freund2014-06-28
| | | | | | | | | | | | | Support for running postgres on Alpha hasn't been tested for a long while. Due to Alpha's uniquely lax cache coherency model it's a hard to develop for platform (especially blindly!) and thought to be unlikely to currently work correctly. As Alpha is the only supported architecture for Tru64 drop support for it as well. Tru64's support has ended 2012 and it has been in maintenance-only mode for much longer. Also remove stray references to __ksr__ and ultrix defines.
* Allow pushdown of WHERE quals into subqueries with window functions.Tom Lane2014-06-27
| | | | | | | | | | | | | | | | | | | | | | | | We can allow this even without any specific knowledge of the semantics of the window function, so long as pushed-down quals will either accept every row in a given window partition, or reject every such row. Because window functions act only within a partition, such a case can't result in changing the window functions' outputs for any surviving row. Eliminating entire partitions in this way obviously can reduce the cost of the window-function computations substantially. The fly in the ointment is that it's hard to be entirely sure whether this is true for an arbitrary qual condition. This patch allows pushdown if (a) the qual references only partitioning columns, and (b) the qual contains no volatile functions. We are at risk of incorrect results if the qual can produce different answers for values that the partitioning equality operator sees as equal. While it's not hard to invent cases for which that can happen, it seems to seldom be a problem in practice, since no one has complained about a similar assumption that we've had for many years with respect to DISTINCT. The potential performance gains seem to be worth the risk. David Rowley, reviewed by Vik Fearing; some credit is due also to Thomas Mayer who did considerable preliminary investigation.
* Have multixact be truncated by checkpoint, not vacuumAlvaro Herrera2014-06-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | Instead of truncating pg_multixact at vacuum time, do it only at checkpoint time. The reason for doing it this way is twofold: first, we want it to delete only segments that we're certain will not be required if there's a crash immediately after the removal; and second, we want to do it relatively often so that older files are not left behind if there's an untimely crash. Per my proposal in http://www.postgresql.org/message-id/20140626044519.GJ7340@eldon.alvh.no-ip.org we now execute the truncation in the checkpointer process rather than as part of vacuum. Vacuum is in only charge of maintaining in shared memory the value to which it's possible to truncate the files; that value is stored as part of checkpoints also, and so upon recovery we can reuse the same value to re-execute truncate and reset the oldest-value-still-safe-to-use to one known to remain after truncation. Per bug reported by Jeff Janes in the course of his tests involving bug #8673. While at it, update some comments that hadn't been updated since multixacts were changed. Backpatch to 9.3, where persistency of pg_multixact files was introduced by commit 0ac5ad5134f2.
* Don't allow relminmxid to go backwards during VACUUM FULLAlvaro Herrera2014-06-27
| | | | | | | | | | | | | We were allowing a table's pg_class.relminmxid value to move backwards when heaps were swapped by VACUUM FULL or CLUSTER. There is a similar protection against relfrozenxid going backwards, which we neglected to clone when the multixact stuff was rejiggered by commit 0ac5ad5134f276. Backpatch to 9.3, where relminmxid was introduced. As reported by Heikki in http://www.postgresql.org/message-id/52401AEA.9000608@vmware.com