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* Add a materialized view relations.Kevin Grittner2013-03-03
| | | | | | | | | | | | | | | | | | | | | | A materialized view has a rule just like a view and a heap and other physical properties like a table. The rule is only used to populate the table, references in queries refer to the materialized data. This is a minimal implementation, but should still be useful in many cases. Currently data is only populated "on demand" by the CREATE MATERIALIZED VIEW and REFRESH MATERIALIZED VIEW statements. It is expected that future releases will add incremental updates with various timings, and that a more refined concept of defining what is "fresh" data will be developed. At some point it may even be possible to have queries use a materialized in place of references to underlying tables, but that requires the other above-mentioned features to be working first. Much of the documentation work by Robert Haas. Review by Noah Misch, Thom Brown, Robert Haas, Marko Tiikkaja Security review by KaiGai Kohei, with a decision on how best to implement sepgsql still pending.
* Fix SQL function execution to be safe with long-lived FmgrInfos.Tom Lane2013-03-03
| | | | | | | | | | | | fmgr_sql had been designed on the assumption that the FmgrInfo it's called with has only query lifespan. This is demonstrably unsafe in connection with range types, as shown in bug #7881 from Andrew Gierth. Fix things so that we re-generate the function's cache data if the (sub)transaction it was made in is no longer active. Back-patch to 9.2. This might be needed further back, but it's not clear whether the case can realistically arise without range types, so for now I'll desist from back-patching further.
* Fix performance issue in EXPLAIN (ANALYZE, TIMING OFF).Tom Lane2013-02-07
| | | | | | | | | | | | | | | | | | | Commit af7914c6627bcf0b0ca614e9ce95d3f8056602bf, which added the TIMING option to EXPLAIN, had an oversight: if the TIMING option is disabled then control in InstrStartNode() goes through an elog(DEBUG2) call, which typically does nothing but takes a noticeable amount of time to do it. Tweak the logic to avoid that. In HEAD, also change the elog(DEBUG2)'s in instrument.c to elog(ERROR). It's not very clear why they weren't like that to begin with, but this episode shows that not complaining more vociferously about misuse is likely to do little except allow bugs to remain hidden. While at it, adjust some code that was making possibly-dangerous assumptions about flag bits being in the rightmost byte of the instrument_options word. Problem reported by Pavel Stehule (via Tomas Vondra).
* Fix plpgsql's reporting of plan-time errors in possibly-simple expressions.Tom Lane2013-01-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | exec_simple_check_plan and exec_eval_simple_expr attempted to call GetCachedPlan directly. This meant that if an error was thrown during planning, the resulting context traceback would not include the line normally contributed by _SPI_error_callback. This is already inconsistent, but just to be really odd, a re-execution of the very same expression *would* show the additional context line, because we'd already have cached the plan and marked the expression as non-simple. The problem is easy to demonstrate in 9.2 and HEAD because planning of a cached plan doesn't occur at all until GetCachedPlan is done. In earlier versions, it could only be an issue if initial planning had succeeded, then a replan was forced (already somewhat improbable for a simple expression), and the replan attempt failed. Since the issue is mainly cosmetic in older branches anyway, it doesn't seem worth the risk of trying to fix it there. It is worth fixing in 9.2 since the instability of the context printout can affect the results of GET STACKED DIAGNOSTICS, as per a recent discussion on pgsql-novice. To fix, introduce a SPI function that wraps GetCachedPlan while installing the correct callback function. Use this instead of calling GetCachedPlan directly from plpgsql. Also introduce a wrapper function for extracting a SPI plan's CachedPlanSource list. This lets us stop including spi_priv.h in pl_exec.c, which was never a very good idea from a modularity standpoint. In passing, fix a similar inconsistency that could occur in SPI_cursor_open, which was also calling GetCachedPlan without setting up a context callback.
* Provide database object names as separate fields in error messages.Tom Lane2013-01-29
| | | | | | | | | | | | | | | | | | This patch addresses the problem that applications currently have to extract object names from possibly-localized textual error messages, if they want to know for example which index caused a UNIQUE_VIOLATION failure. It adds new error message fields to the wire protocol, which can carry the name of a table, table column, data type, or constraint associated with the error. (Since the protocol spec has always instructed clients to ignore unrecognized field types, this should not create any compatibility problem.) Support for providing these new fields has been added to just a limited set of error reports (mainly, those in the "integrity constraint violation" SQLSTATE class), but we will doubtless add them to more calls in future. Pavel Stehule, reviewed and extensively revised by Peter Geoghegan, with additional hacking by Tom Lane.
* Fix SPI documentation for new handling of ExecutorRun's count parameter.Tom Lane2013-01-24
| | | | | | | | | | | | | | Since 9.0, the count parameter has only limited the number of tuples actually returned by the executor. It doesn't affect the behavior of INSERT/UPDATE/DELETE unless RETURNING is specified, because without RETURNING, the ModifyTable plan node doesn't return control to execMain.c for each tuple. And we only check the limit at the top level. While this behavioral change was unintentional at the time, discussion of bug #6572 led us to the conclusion that we prefer the new behavior anyway, and so we should just adjust the docs to match rather than change the code. Accordingly, do that. Back-patch as far as 9.0 so that the docs match the code in each branch.
* Improve concurrency of foreign key lockingAlvaro Herrera2013-01-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduces two additional lock modes for tuples: "SELECT FOR KEY SHARE" and "SELECT FOR NO KEY UPDATE". These don't block each other, in contrast with already existing "SELECT FOR SHARE" and "SELECT FOR UPDATE". UPDATE commands that do not modify the values stored in the columns that are part of the key of the tuple now grab a SELECT FOR NO KEY UPDATE lock on the tuple, allowing them to proceed concurrently with tuple locks of the FOR KEY SHARE variety. Foreign key triggers now use FOR KEY SHARE instead of FOR SHARE; this means the concurrency improvement applies to them, which is the whole point of this patch. The added tuple lock semantics require some rejiggering of the multixact module, so that the locking level that each transaction is holding can be stored alongside its Xid. Also, multixacts now need to persist across server restarts and crashes, because they can now represent not only tuple locks, but also tuple updates. This means we need more careful tracking of lifetime of pg_multixact SLRU files; since they now persist longer, we require more infrastructure to figure out when they can be removed. pg_upgrade also needs to be careful to copy pg_multixact files over from the old server to the new, or at least part of multixact.c state, depending on the versions of the old and new servers. Tuple time qualification rules (HeapTupleSatisfies routines) need to be careful not to consider tuples with the "is multi" infomask bit set as being only locked; they might need to look up MultiXact values (i.e. possibly do pg_multixact I/O) to find out the Xid that updated a tuple, whereas they previously were assured to only use information readily available from the tuple header. This is considered acceptable, because the extra I/O would involve cases that would previously cause some commands to block waiting for concurrent transactions to finish. Another important change is the fact that locking tuples that have previously been updated causes the future versions to be marked as locked, too; this is essential for correctness of foreign key checks. This causes additional WAL-logging, also (there was previously a single WAL record for a locked tuple; now there are as many as updated copies of the tuple there exist.) With all this in place, contention related to tuples being checked by foreign key rules should be much reduced. As a bonus, the old behavior that a subtransaction grabbing a stronger tuple lock than the parent (sub)transaction held on a given tuple and later aborting caused the weaker lock to be lost, has been fixed. Many new spec files were added for isolation tester framework, to ensure overall behavior is sane. There's probably room for several more tests. There were several reviewers of this patch; in particular, Noah Misch and Andres Freund spent considerable time in it. Original idea for the patch came from Simon Riggs, after a problem report by Joel Jacobson. Most code is from me, with contributions from Marti Raudsepp, Alexander Shulgin, Noah Misch and Andres Freund. This patch was discussed in several pgsql-hackers threads; the most important start at the following message-ids: AANLkTimo9XVcEzfiBR-ut3KVNDkjm2Vxh+t8kAmWjPuv@mail.gmail.com 1290721684-sup-3951@alvh.no-ip.org 1294953201-sup-2099@alvh.no-ip.org 1320343602-sup-2290@alvh.no-ip.org 1339690386-sup-8927@alvh.no-ip.org 4FE5FF020200002500048A3D@gw.wicourts.gov 4FEAB90A0200002500048B7D@gw.wicourts.gov
* Fix obsolete SQL syntax in comment.Tom Lane2013-01-14
| | | | | | | This was legal back in the days of add_missing_from, though perhaps never good style. It's not legal anymore ... Jan Urbański
* Invent a "one-shot" variant of CachedPlans for better performance.Tom Lane2013-01-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | SPI_execute() and related functions create a CachedPlan, execute it once, and immediately discard it, so that the functionality offered by plancache.c is of no value in this code path. And performance measurements show that the extra data copying and invalidation checking done by plancache.c slows down simple queries by 10% or more compared to 9.1. However, enough of the SPI code is shared with functions that do need plan caching that it seems impractical to bypass plancache.c altogether. Instead, let's invent a variant version of cached plans that preserves 99% of the API but doesn't offer any of the actual functionality, nor the overhead. This puts SPI_execute() performance back on par, or maybe even slightly better, than it was before. This change should resolve recent complaints of performance degradation from Dong Ye, Pavel Stehule, and others. By avoiding data copying, this change also reduces the amount of memory needed to execute many-statement SPI_execute() strings, as for instance in a recent complaint from Tomas Vondra. An additional benefit of this change is that multi-statement SPI_execute() query strings are now processed fully serially, that is we complete execution of earlier statements before running parse analysis and planning on following ones. This eliminates a long-standing POLA violation, in that DDL that affects the behavior of a later statement will now behave as expected. Back-patch to 9.2, since this was a performance regression compared to 9.1. (In 9.2, place the added struct fields so as to avoid changing the offsets of existing fields.) Heikki Linnakangas and Tom Lane
* Update copyrights for 2013Bruce Momjian2013-01-01
| | | | | Fully update git head, and update back branches in ./COPYRIGHT and legal.sgml files.
* Add defenses against integer overflow in dynahash numbuckets calculations.Tom Lane2012-12-11
| | | | | | | | | | | | | | | The dynahash code requires the number of buckets in a hash table to fit in an int; but since we calculate the desired hash table size dynamically, there are various scenarios where we might calculate too large a value. The resulting overflow can lead to infinite loops, division-by-zero crashes, etc. I (tgl) had previously installed some defenses against that in commit 299d1716525c659f0e02840e31fbe4dea3, but that covered only one call path. Moreover it worked by limiting the request size to work_mem, but in a 64-bit machine it's possible to set work_mem high enough that the problem appears anyway. So let's fix the problem at the root by installing limits in the dynahash.c functions themselves. Trouble report and patch by Jeff Davis.
* Support automatically-updatable views.Tom Lane2012-12-08
| | | | | | | | | | | | | | | | | This patch makes "simple" views automatically updatable, without the need to create either INSTEAD OF triggers or INSTEAD rules. "Simple" views are those classified as updatable according to SQL-92 rules. The rewriter transforms INSERT/UPDATE/DELETE commands on such views directly into an equivalent command on the underlying table, which will generally have noticeably better performance than is possible with either triggers or user-written rules. A view that has INSTEAD OF triggers or INSTEAD rules continues to operate the same as before. For the moment, security_barrier views are not considered simple. Also, we do not support WITH CHECK OPTION. These features may be added in future. Dean Rasheed, reviewed by Amit Kapila
* Basic binary heap implementation.Robert Haas2012-11-29
| | | | | | | | | | There are probably other places where this can be used, but for now, this just makes MergeAppend use it, so that this code will have test coverage. There is other work in the queue that will use this, as well. Abhijit Menon-Sen, reviewed by Andres Freund, Robert Haas, Álvaro Herrera, Tom Lane, and others.
* Fix assorted bugs in CREATE/DROP INDEX CONCURRENTLY.Tom Lane2012-11-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 8cb53654dbdb4c386369eb988062d0bbb6de725e, which introduced DROP INDEX CONCURRENTLY, managed to break CREATE INDEX CONCURRENTLY via a poor choice of catalog state representation. The pg_index state for an index that's reached the final pre-drop stage was the same as the state for an index just created by CREATE INDEX CONCURRENTLY. This meant that the (necessary) change to make RelationGetIndexList ignore about-to-die indexes also made it ignore freshly-created indexes; which is catastrophic because the latter do need to be considered in HOT-safety decisions. Failure to do so leads to incorrect index entries and subsequently wrong results from queries depending on the concurrently-created index. To fix, add an additional boolean column "indislive" to pg_index, so that the freshly-created and about-to-die states can be distinguished. (This change obviously is only possible in HEAD. This patch will need to be back-patched, but in 9.2 we'll use a kluge consisting of overloading the formerly-impossible state of indisvalid = true and indisready = false.) In addition, change CREATE/DROP INDEX CONCURRENTLY so that the pg_index flag changes they make without exclusive lock on the index are made via heap_inplace_update() rather than a normal transactional update. The latter is not very safe because moving the pg_index tuple could result in concurrent SnapshotNow scans finding it twice or not at all, thus possibly resulting in index corruption. This is a pre-existing bug in CREATE INDEX CONCURRENTLY, which was copied into the DROP code. In addition, fix various places in the code that ought to check to make sure that the indexes they are manipulating are valid and/or ready as appropriate. These represent bugs that have existed since 8.2, since a failed CREATE INDEX CONCURRENTLY could leave a corrupt or invalid index behind, and we ought not try to do anything that might fail with such an index. Also fix RelationReloadIndexInfo to ensure it copies all the pg_index columns that are allowed to change after initial creation. Previously we could have been left with stale values of some fields in an index relcache entry. It's not clear whether this actually had any user-visible consequences, but it's at least a bug waiting to happen. In addition, do some code and docs review for DROP INDEX CONCURRENTLY; some cosmetic code cleanup but mostly addition and revision of comments. This will need to be back-patched, but in a noticeably different form, so I'm committing it to HEAD before working on the back-patch. Problem reported by Amit Kapila, diagnosis by Pavan Deolassee, fix by Tom Lane and Andres Freund.
* Revert patch for taking fewer snapshots.Tom Lane2012-11-26
| | | | | | | | | | | | | This reverts commit d573e239f03506920938bf0be56c868d9c3416da, "Take fewer snapshots". While that seemed like a good idea at the time, it caused execution to use a snapshot that had been acquired before locking any of the tables mentioned in the query. This created user-visible anomalies that were not present in any prior release of Postgres, as reported by Tomas Vondra. While this whole area could do with a redesign (since there are related cases that have anomalies anyway), it doesn't seem likely that any future patch would be reasonably back-patchable; and we don't want 9.2 to exhibit a behavior that's subtly unlike either past or future releases. Hence, revert to prior code while we rethink the problem.
* Throw error if expiring tuple is again updated or deleted.Kevin Grittner2012-10-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This prevents surprising behavior when a FOR EACH ROW trigger BEFORE UPDATE or BEFORE DELETE directly or indirectly updates or deletes the the old row. Prior to this patch the requested action on the row could be silently ignored while all triggered actions based on the occurence of the requested action could be committed. One example of how this could happen is if the BEFORE DELETE trigger for a "parent" row deleted "children" which had trigger functions to update summary or status data on the parent. This also prevents similar surprising problems if the query has a volatile function which updates a target row while it is already being updated. There are related issues present in FOR UPDATE cursors and READ COMMITTED queries which are not handled by this patch. These issues need further evalution to determine what change, if any, is needed. Where the new error messages are generated, in most cases the best fix will be to move code from the BEFORE trigger to an AFTER trigger. Where this is not feasible, the trigger can avoid the error by re-issuing the triggering statement and returning NULL. Documentation changes will be submitted in a separate patch. Kevin Grittner and Tom Lane with input from Florian Pflug and Robert Haas, based on problems encountered during conversion of Wisconsin Circuit Court trigger logic to plpgsql triggers.
* Get rid of COERCE_DONTCARE.Tom Lane2012-10-12
| | | | We don't need this hack any more.
* Fix cross-type case in partial row matching for hashed subplans.Tom Lane2012-10-11
| | | | | | | | | | | | | | When hashing a subplan like "WHERE (a, b) NOT IN (SELECT x, y FROM ...)", findPartialMatch() attempted to match rows using the hashtable's internal equality operators, which of course are for x and y's datatypes. What we need to use are the potentially cross-type operators for a=x, b=y, etc. Failure to do that leads to wrong answers or even crashes. The scope for problems is limited to cases where we have different types with compatible hash functions (else we'd not be using a hashed subplan), but for example int4 vs int8 can cause the problem. Per bug #7597 from Bo Jensen. This has been wrong since the hashed-subplan code was written, so patch all the way back.
* Return the number of rows processed when COPY is executed through SPI.Heikki Linnakangas2012-10-03
| | | | | | | You can now get the number of rows processed by a COPY statement in a PL/pgSQL function with "GET DIAGNOSTICS x = ROW_COUNT". Pavel Stehule, reviewed by Amit Kapila, with some editing by me.
* Fix serializable mode with index-only scans.Kevin Grittner2012-09-04
| | | | | | | | | | | | | | | | | | | | | | | | | | Serializable Snapshot Isolation used for serializable transactions depends on acquiring SIRead locks on all heap relation tuples which are used to generate the query result, so that a later delete or update of any of the tuples can flag a read-write conflict between transactions. This is normally handled in heapam.c, with tuple level locking. Since an index-only scan avoids heap access in many cases, building the result from the index tuple, the necessary predicate locks were not being acquired for all tuples in an index-only scan. To prevent problems with tuple IDs which are vacuumed and re-used while the transaction still matters, the xmin of the tuple is part of the tag for the tuple lock. Since xmin is not available to the index-only scan for result rows generated from the index tuples, it is not possible to acquire a tuple-level predicate lock in such cases, in spite of having the tid. If we went to the heap to get the xmin value, it would no longer be an index-only scan. Rather than prohibit index-only scans under serializable transaction isolation, we acquire an SIRead lock on the page containing the tuple, when it was not necessary to visit the heap for other reasons. Backpatch to 9.2. Kevin Grittner and Tom Lane
* Split tuple struct defs from htup.h to htup_details.hAlvaro Herrera2012-08-30
| | | | | | | | | | | | This reduces unnecessary exposure of other headers through htup.h, which is very widely included by many files. I have chosen to move the function prototypes to the new file as well, because that means htup.h no longer needs to include tupdesc.h. In itself this doesn't have much effect in indirect inclusion of tupdesc.h throughout the tree, because it's also required by execnodes.h; but it's something to explore in the future, and it seemed best to do the htup.h change now while I'm busy with it.
* Split heapam_xlog.h from heapam.hAlvaro Herrera2012-08-28
| | | | | | | | | | | | The heapam XLog functions are used by other modules, not all of which are interested in the rest of the heapam API. With this, we let them get just the XLog stuff in which they are interested and not pollute them with unrelated includes. Also, since heapam.h no longer requires xlog.h, many files that do include heapam.h no longer get xlog.h automatically, including a few headers. This is useful because heapam.h is getting pulled in by execnodes.h, which is in turn included by a lot of files.
* Fix rescan logic in nodeCtescan.Tom Lane2012-08-15
| | | | | | | | | | | | | | | | | | | | | | The previous coding essentially assumed that nodes would be rescanned in the same order they were initialized in; or at least that the "leader" of a group of CTEscans would be rescanned before any others were required to execute. Unfortunately, that isn't even a little bit true. It's possible to devise queries in which the leader isn't rescanned until other CTEscans on the same CTE have run to completion, or even in which the leader never gets a rescan call at all. The fix makes the leader specially responsible only for initial creation and final destruction of the tuplestore; rescan resets are now a symmetrically shared responsibility. This means that we might reset the tuplestore multiple times when restarting a plan subtree containing multiple CTEscans; but resetting an already-empty tuplestore is cheap enough that that doesn't seem like a problem. Per report from Adam Mackler; the new regression test cases are based on his example query. Back-patch to 8.4 where CTE scans were introduced.
* Fix whole-row Var evaluation to cope with resjunk columns (again).Tom Lane2012-07-20
| | | | | | | | | | | | | | | | | | When a whole-row Var is reading the result of a subquery, we need it to ignore any "resjunk" columns that the subquery might have evaluated for GROUP BY or ORDER BY purposes. We've hacked this area before, in commit 68e40998d058c1f6662800a648ff1e1ce5d99cba, but that fix only covered whole-row Vars of named composite types, not those of RECORD type; and it was mighty klugy anyway, since it just assumed without checking that any extra columns in the result must be resjunk. A proper fix requires getting hold of the subquery's targetlist so we can actually see which columns are resjunk (whereupon we can use a JunkFilter to get rid of them). So bite the bullet and add some infrastructure to make that possible. Per report from Andrew Dunstan and additional testing by Merlin Moncure. Back-patch to all supported branches. In 8.3, also back-patch commit 292176a118da6979e5d368a4baf27f26896c99a5, which for some reason I had not done at the time, but it's a prerequisite for this change.
* Make new event trigger facility actually do something.Robert Haas2012-07-20
| | | | | | | | | | | | | | | | Commit 3855968f328918b6cd1401dd11d109d471a54d40 added syntax, pg_dump, psql support, and documentation, but the triggers didn't actually fire. With this commit, they now do. This is still a pretty basic facility overall because event triggers do not get a whole lot of information about what the user is trying to do unless you write them in C; and there's still no option to fire them anywhere except at the very beginning of the execution sequence, but it's better than nothing, and a good building block for future work. Along the way, add a regression test for ALTER LARGE OBJECT, since testing of event triggers reveals that we haven't got one. Dimitri Fontaine and Robert Haas
* Remove unreachable codePeter Eisentraut2012-07-16
| | | | | | | The Solaris Studio compiler warns about these instances, unlike more mainstream compilers such as gcc. But manual inspection showed that the code is clearly not reachable, and we hope no worthy compiler will complain about removing this code.
* Fix memory leak in ARRAY(SELECT ...) subqueries.Tom Lane2012-06-21
| | | | | | | | | | | Repeated execution of an uncorrelated ARRAY_SUBLINK sub-select (which I think can only happen if the sub-select is embedded in a larger, correlated subquery) would leak memory for the duration of the query, due to not reclaiming the array generated in the previous execution. Per bug #6698 from Armando Miraglia. Diagnosis and fix idea by Heikki, patch itself by me. This has been like this all along, so back-patch to all supported versions.
* Run pgindent on 9.2 source tree in preparation for first 9.3Bruce Momjian2012-06-10
| | | | commit-fest.
* Fix more crash-safe visibility map bugs, and improve comments.Robert Haas2012-06-07
| | | | | | | | | | | | | | | | | | | | | | | | | In lazy_scan_heap, we could issue bogus warnings about incorrect information in the visibility map, because we checked the visibility map bit before locking the heap page, creating a race condition. Fix by rechecking the visibility map bit before we complain. Rejigger some related logic so that we rely on the possibly-outdated all_visible_according_to_vm value as little as possible. In heap_multi_insert, it's not safe to clear the visibility map bit before beginning the critical section. The visibility map is not crash-safe unless we treat clearing the bit as a critical operation. Specifically, if the transaction were to error out after we set the bit and before entering the critical section, we could end up writing the heap page to disk (with the bit cleared) and crashing before the visibility map page made it to disk. That would be bad. heap_insert has this correct, but somehow the order of operations got rearranged when heap_multi_insert was added. Also, add some more comments to visibilitymap_test, lazy_scan_heap, and IndexOnlyNext, expounding on concurrency issues. Per extensive code review by Andres Freund, and further review by Tom Lane, who also made the original report about the bogus warnings.
* Rename I/O timing statistics columns to blk_read_time and blk_write_time.Tom Lane2012-04-29
| | | | | This seems more consistent with the pre-existing choices for names of other statistics columns. Rename assorted internal identifiers to match.
* Lots of doc corrections.Robert Haas2012-04-23
| | | | Josh Kupershmidt
* New GUC, track_iotiming, to track I/O timings.Robert Haas2012-03-27
| | | | | | | | Currently, the only way to see the numbers this gathers is via EXPLAIN (ANALYZE, BUFFERS), but the plan is to add visibility through the stats collector and pg_stat_statements in subsequent patches. Ants Aasma, reviewed by Greg Smith, with some further changes by me.
* Clean up compiler warnings from unused variables with asserts disabledPeter Eisentraut2012-03-21
| | | | | | For those variables only used when asserts are enabled, use a new macro PG_USED_FOR_ASSERTS_ONLY, which expands to __attribute__((unused)) when asserts are not enabled.
* Restructure SELECT INTO's parsetree representation into CreateTableAsStmt.Tom Lane2012-03-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | Making this operation look like a utility statement seems generally a good idea, and particularly so in light of the desire to provide command triggers for utility statements. The original choice of representing it as SELECT with an IntoClause appendage had metastasized into rather a lot of places, unfortunately, so that this patch is a great deal more complicated than one might at first expect. In particular, keeping EXPLAIN working for SELECT INTO and CREATE TABLE AS subcommands required restructuring some EXPLAIN-related APIs. Add-on code that calls ExplainOnePlan or ExplainOneUtility, or uses ExplainOneQuery_hook, will need adjustment. Also, the cases PREPARE ... SELECT INTO and CREATE RULE ... SELECT INTO, which formerly were accepted though undocumented, are no longer accepted. The PREPARE case can be replaced with use of CREATE TABLE AS EXECUTE. The CREATE RULE case doesn't seem to have much real-world use (since the rule would work only once before failing with "table already exists"), so we'll not bother with that one. Both SELECT INTO and CREATE TABLE AS still return a command tag of "SELECT nnnn". There was some discussion of returning "CREATE TABLE nnnn", but for the moment backwards compatibility wins the day. Andres Freund and Tom Lane
* Make EXPLAIN (BUFFERS) track blocks dirtied, as well as those written.Robert Haas2012-02-22
| | | | | | Also expose the new counters through pg_stat_statements. Patch by me. Review by Fujii Masao and Greg Smith.
* Preserve column names in the execution-time tupledesc for a RowExpr.Tom Lane2012-02-14
| | | | | | | | | | | | | | | The hstore and json datatypes both have record-conversion functions that pay attention to column names in the composite values they're handed. We used to not worry about inserting correct field names into tuple descriptors generated at runtime, but given these examples it seems useful to do so. Observe the nicer-looking results in the regression tests whose results changed. catversion bump because there is a subtle change in requirements for stored rule parsetrees: RowExprs from ROW() constructs now have to include field names. Andrew Dunstan and Tom Lane
* Add TIMING option to EXPLAIN, to allow eliminating of timing overhead.Robert Haas2012-02-07
| | | | | | | | Sometimes it may be useful to get actual row counts out of EXPLAIN (ANALYZE) without paying the cost of timing every node entry/exit. With this patch, you can say EXPLAIN (ANALYZE, TIMING OFF) to get that. Tomas Vondra, reviewed by Eric Theise, with minor doc changes by me.
* Allow SQL-language functions to reference parameters by name.Tom Lane2012-02-04
| | | | Matthew Draper, reviewed by Hitoshi Harada
* Assorted comment fixes, mostly just typos, but some obsolete statements.Tom Lane2012-01-29
| | | | YAMAMOTO Takashi
* Fix handling of data-modifying CTE subplans in EvalPlanQual.Tom Lane2012-01-28
| | | | | | | | | | | | | | | We can't just skip initializing such subplans, because the referencing CTE node will expect to find the subplan available when it initializes. That in turn means that ExecInitModifyTable must allow the case (which actually it needed to do anyway, since there's no guarantee that ModifyTable is exactly at the top of the CTE plan tree). So move the complaint about not being allowed in EvalPlanQual mode to execution instead of initialization. Testing turned up yet another problem, which is that we'd try to re-initialize the result relation's index list, leading to leaks and dangling pointers. Per report from Phil Sorber. Back-patch to 9.1 where data-modifying CTEs were introduced.
* Instrument index-only scans to count heap fetches performed.Robert Haas2012-01-25
| | | | Patch by me; review by Tom Lane, Jeff Davis, and Peter Geoghegan.
* Prevent adding relations to a concurrently dropped schema.Robert Haas2012-01-16
| | | | | | | | | | | | | | | | | | | | | | | | | In the previous coding, it was possible for a relation to be created via CREATE TABLE, CREATE VIEW, CREATE SEQUENCE, CREATE FOREIGN TABLE, etc. in a schema while that schema was meanwhile being concurrently dropped. This led to a pg_class entry with an invalid relnamespace value. The same problem could occur if a relation was moved using ALTER .. SET SCHEMA while the target schema was being concurrently dropped. This patch prevents both of those scenarios by locking the schema to which the relation is being added using AccessShareLock, which conflicts with the AccessExclusiveLock taken by DROP. As a desirable side effect, this also prevents the use of CREATE OR REPLACE VIEW to queue for an AccessExclusiveLock on a relation on which you have no rights: that will now fail immediately with a permissions error, before trying to obtain a lock. We need similar protection for all other object types, but as everything other than relations uses a slightly different set of code paths, I'm leaving that for a separate commit. Original complaint (as far as I could find) about CREATE by Nikhil Sontakke; risk for ALTER .. SET SCHEMA pointed out by Tom Lane; further details by Dan Farina; patch by me; review by Hitoshi Harada.
* Make executor's SELECT INTO code save and restore original tuple receiver.Tom Lane2012-01-04
| | | | | | | | | | | | As previously coded, the QueryDesc's dest pointer was left dangling (pointing at an already-freed receiver object) after ExecutorEnd. It's a bit astonishing that it took us this long to notice, and I'm not sure that the known problem case with SQL functions is the only one. Fix it by saving and restoring the original receiver pointer, which seems the most bulletproof way of ensuring any related bugs are also covered. Per bug #6379 from Paul Ramsey. Back-patch to 8.4 where the current handling of SELECT INTO was introduced.
* Update copyright notices for year 2012.Bruce Momjian2012-01-01
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* Take fewer snapshots.Robert Haas2011-12-21
| | | | | | | | | | | | | | | | | | | When a PORTAL_ONE_SELECT query is executed, we can opportunistically reuse the parse/plan shot for the execution phase. This cuts down the number of snapshots per simple query from 2 to 1 for the simple protocol, and 3 to 2 for the extended protocol. Since we are only reusing a snapshot taken early in the processing of the same protocol message, the change shouldn't be user-visible, except that the remote possibility of the planning and execution snapshots being different is eliminated. Note that this change does not make it safe to assume that the parse/plan snapshot will certainly be reused; that will currently only happen if PortalStart() decides to use the PORTAL_ONE_SELECT strategy. It might be worth trying to provide some stronger guarantees here in the future, but for now we don't. Patch by me; review by Dimitri Fontaine.
* Add support for privileges on typesPeter Eisentraut2011-12-20
| | | | | | | | | This adds support for the more or less SQL-conforming USAGE privilege on types and domains. The intent is to be able restrict which users can create dependencies on types, which restricts the way in which owners can alter types. reviewed by Yeb Havinga
* Miscellaneous cleanup to silence compiler warnings seen on Mingw.Andrew Dunstan2011-12-10
| | | | | Remove some dead code, conditionally declare some items or call some code, and fix one or two declarations.
* Create a "sort support" interface API for faster sorting.Tom Lane2011-12-07
| | | | | | | | | | | | This patch creates an API whereby a btree index opclass can optionally provide non-SQL-callable support functions for sorting. In the initial patch, we only use this to provide a directly-callable comparator function, which can be invoked with a bit less overhead than the traditional SQL-callable comparator. While that should be of value in itself, the real reason for doing this is to provide a datatype-extensible framework for more aggressive optimizations, as in Peter Geoghegan's recent work. Robert Haas and Tom Lane
* When a row fails a not-null constraint, show row's contents in errdetail.Tom Lane2011-11-29
| | | | Simple extension of previous patch for CHECK constraints.
* When a row fails a CHECK constraint, show row's contents in errdetail.Tom Lane2011-11-29
| | | | | | | | | | | | This should make it easier to identify which row is problematic when an insert or update is processing many rows. The formatting is similar to that for unique-index violation messages, except that we limit field widths to 64 bytes since otherwise the message could get unreasonably long. (In particular, there's currently no attempt to quote or escape field values that contain commas etc.) Jan Kundrát, reviewed by Royce Ausburn, somewhat rewritten by me.