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* Rename assorted LWLock tranches.Tom Lane2020-05-15
| | | | | | | | | | | | | | | | Choose names that fit into the conventions for wait event names (particularly, that multi-word names are in the style MultiWordName) and hopefully convey more information to non-hacker users than the previous names did. Also rename SerializablePredicateLockListLock to SerializablePredicateListLock; the old name was long enough to cause table formatting problems, plus the double occurrence of "Lock" seems confusing/error-prone. Also change a couple of particularly opaque LWLock field names. Discussion: https://postgr.es/m/28683.1589405363@sss.pgh.pa.us
* Allow ALTER TYPE to change some properties of a base type.Tom Lane2020-03-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Specifically, this patch allows ALTER TYPE to: * Change the default TOAST strategy for a toastable base type; * Promote a non-toastable type to toastable; * Add/remove binary I/O functions for a type; * Add/remove typmod I/O functions for a type; * Add/remove a custom ANALYZE statistics functions for a type. The first of these can be done by the type's owner; all the others require superuser privilege since misuse could cause problems. The main motivation for this patch is to allow extensions to upgrade the feature sets of their data types, so the set of alterable properties is biased towards that use-case. However it's also true that changing some other properties would be a lot harder, as they get baked into physical storage and/or stored expressions that depend on the type. Along the way, refactor GenerateTypeDependencies() to make it easier to call, refactor DefineType's volatility checks so they can be shared by AlterType, and teach typcache.c that it might have to reload data from the type's pg_type row, a scenario it never handled before. Also rearrange alter_type.sgml a bit for clarity (put the composite-type operations together). Tomas Vondra and Tom Lane Discussion: https://postgr.es/m/20200228004440.b23ein4qvmxnlpht@development
* Update copyrights for 2020Bruce Momjian2020-01-01
| | | | Backpatch-through: update all files in master, backpatch legal files through 9.4
* Fix plpgsql to re-look-up composite type names at need.Tom Lane2019-08-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 4b93f5799 rearranged things in plpgsql to make it cope better with composite types changing underneath it intra-session. However, I failed to consider the case of a composite type being dropped and recreated entirely. In my defense, the previous coding didn't consider that possibility at all either --- but it would accidentally work so long as you didn't change the type's field list, because the built-at-compile-time list of component variables would then still match the type's new definition. The new coding, however, occasionally tries to re-look-up the type by OID, and then fails to find the dropped type. To fix this, we need to save the TypeName struct, and then redo the type OID lookup from that. Of course that's expensive, so we don't want to do it every time we need the type OID. This can be fixed in the same way that 4b93f5799 dealt with changes to composite types' definitions: keep an eye on the type's typcache entry to see if its tupledesc has been invalidated. (Perhaps, at some point, this mechanism should be generalized so it can work for non-composite types too; but for now, plpgsql only tries to cope with intra-session redefinitions of composites.) I'm slightly hesitant to back-patch this into v11, because it changes the contents of struct PLpgSQL_type as well as the signature of plpgsql_build_datatype(), so in principle it could break code that is poking into the innards of plpgsql. However, the only popular extension of that ilk is pldebugger, and it doesn't seem to be affected. Since this is a regression for people who were relying on the old behavior, it seems worth taking the small risk of causing compatibility issues. Per bug #15913 from Daniel Fiori. Back-patch to v11 where 4b93f5799 came in. Discussion: https://postgr.es/m/15913-a7e112e16dedcffc@postgresql.org
* Phase 2 pgindent run for v12.Tom Lane2019-05-22
| | | | | | | | | Switch to 2.1 version of pg_bsd_indent. This formats multiline function declarations "correctly", that is with additional lines of parameter declarations indented to match where the first line's left parenthesis is. Discussion: https://postgr.es/m/CAEepm=0P3FeTXRcU5B2W3jv3PgRVZ-kGUXLGfd42FFhUROO3ug@mail.gmail.com
* Refactor planner's header files.Tom Lane2019-01-29
| | | | | | | | | | | | | | | | | | | | | | | | Create a new header optimizer/optimizer.h, which exposes just the planner functions that can be used "at arm's length", without need to access Paths or the other planner-internal data structures defined in nodes/relation.h. This is intended to provide the whole planner API seen by most of the rest of the system; although FDWs still need to use additional stuff, and more thought is also needed about just what selfuncs.c should rely on. The main point of doing this now is to limit the amount of new #include baggage that will be needed by "planner support functions", which I expect to introduce later, and which will be in relevant datatype modules rather than anywhere near the planner. This commit just moves relevant declarations into optimizer.h from other header files (a couple of which go away because everything got moved), and adjusts #include lists to match. There's further cleanup that could be done if we want to decide that some stuff being exposed by optimizer.h doesn't belong in the planner at all, but I'll leave that for another day. Discussion: https://postgr.es/m/11460.1548706639@sss.pgh.pa.us
* Fix misc typos in comments.Heikki Linnakangas2019-01-23
| | | | | | Spotted mostly by Fabien Coelho. Discussion: https://www.postgresql.org/message-id/alpine.DEB.2.21.1901230947050.16643@lancre
* Replace uses of heap_open et al with the corresponding table_* function.Andres Freund2019-01-21
| | | | | Author: Andres Freund Discussion: https://postgr.es/m/20190111000539.xbv7s6w7ilcvm7dp@alap3.anarazel.de
* Replace heapam.h includes with {table, relation}.h where applicable.Andres Freund2019-01-21
| | | | | | | | | A lot of files only included heapam.h for relation_open, heap_open etc - replace the heapam.h include in those files with the narrower header. Author: Andres Freund Discussion: https://postgr.es/m/20190111000539.xbv7s6w7ilcvm7dp@alap3.anarazel.de
* Update copyright for 2019Bruce Momjian2019-01-02
| | | | Backpatch-through: certain files through 9.4
* Make pg_statistic and related code account more honestly for collations.Tom Lane2018-12-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When we first put in collations support, we basically punted on teaching pg_statistic, ANALYZE, and the planner selectivity functions about that. They've just used DEFAULT_COLLATION_OID independently of the actual collation of the data. It's time to improve that, so: * Add columns to pg_statistic that record the specific collation associated with each statistics slot. * Teach ANALYZE to use the column's actual collation when comparing values for statistical purposes, and record this in the appropriate slot. (Note that type-specific typanalyze functions are now expected to fill stats->stacoll with the appropriate collation, too.) * Teach assorted selectivity functions to use the actual collation of the stats they are looking at, instead of just assuming it's DEFAULT_COLLATION_OID. This should give noticeably better results in selectivity estimates for columns with nondefault collations, at least for query clauses that use that same collation (which would be the default behavior in most cases). It's still true that comparisons with explicit COLLATE clauses different from the stored data's collation won't be well-estimated, but that's no worse than before. Also, this patch does make the first step towards doing better with that, which is that it's now theoretically possible to collect stats for a collation other than the column's own collation. Patch by me; thanks to Peter Eisentraut for review. Discussion: https://postgr.es/m/14706.1544630227@sss.pgh.pa.us
* Drop no-op CoerceToDomain nodes from expressions at planning time.Tom Lane2018-12-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a domain has no constraints, then CoerceToDomain doesn't really do anything and can be simplified to a RelabelType. This not only eliminates cycles at execution, but allows the planner to optimize better (for instance, match the coerced expression to an index on the underlying column). However, we do have to support invalidating the plan later if a constraint gets added to the domain. That's comparable to the case of a change to a SQL function that had been inlined into a plan, so all the necessary logic already exists for plans depending on functions. We need only duplicate or share that logic for domains. ALTER DOMAIN ADD/DROP CONSTRAINT need to be taught to send out sinval messages for the domain's pg_type entry, since those operations don't update that row. (ALTER DOMAIN SET/DROP NOT NULL do update that row, so no code change is needed for them.) Testing this revealed what's really a pre-existing bug in plpgsql: it caches the SQL-expression-tree expansion of type coercions and had no provision for invalidating entries in that cache. Up to now that was only a problem if such an expression had inlined a SQL function that got changed, which is unlikely though not impossible. But failing to track changes of domain constraints breaks an existing regression test case and would likely cause practical problems too. We could fix that locally in plpgsql, but what seems like a better idea is to build some generic infrastructure in plancache.c to store standalone expressions and track invalidation events for them. (It's tempting to wonder whether plpgsql's "simple expression" stuff could use this code with lower overhead than its current use of the heavyweight plancache APIs. But I've left that idea for later.) Other stuff fixed in passing: * Allow estimate_expression_value() to drop CoerceToDomain unconditionally, effectively assuming that the coercion will succeed. This will improve planner selectivity estimates for cases involving estimatable expressions that are coerced to domains. We could have done this independently of everything else here, but there wasn't previously any need for eval_const_expressions_mutator to know about CoerceToDomain at all. * Use a dlist for plancache.c's list of cached plans, rather than a manually threaded singly-linked list. That eliminates a potential performance problem in DropCachedPlan. * Fix a couple of inconsistencies in typecmds.c about whether operations on domains drop RowExclusiveLock on pg_type. Our common practice is that DDL operations do drop catalog locks, so standardize on that choice. Discussion: https://postgr.es/m/19958.1544122124@sss.pgh.pa.us
* Remove WITH OIDS support, change oid catalog column visibility.Andres Freund2018-11-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Previously tables declared WITH OIDS, including a significant fraction of the catalog tables, stored the oid column not as a normal column, but as part of the tuple header. This special column was not shown by default, which was somewhat odd, as it's often (consider e.g. pg_class.oid) one of the more important parts of a row. Neither pg_dump nor COPY included the contents of the oid column by default. The fact that the oid column was not an ordinary column necessitated a significant amount of special case code to support oid columns. That already was painful for the existing, but upcoming work aiming to make table storage pluggable, would have required expanding and duplicating that "specialness" significantly. WITH OIDS has been deprecated since 2005 (commit ff02d0a05280e0). Remove it. Removing includes: - CREATE TABLE and ALTER TABLE syntax for declaring the table to be WITH OIDS has been removed (WITH (oids[ = true]) will error out) - pg_dump does not support dumping tables declared WITH OIDS and will issue a warning when dumping one (and ignore the oid column). - restoring an pg_dump archive with pg_restore will warn when restoring a table with oid contents (and ignore the oid column) - COPY will refuse to load binary dump that includes oids. - pg_upgrade will error out when encountering tables declared WITH OIDS, they have to be altered to remove the oid column first. - Functionality to access the oid of the last inserted row (like plpgsql's RESULT_OID, spi's SPI_lastoid, ...) has been removed. The syntax for declaring a table WITHOUT OIDS (or WITH (oids = false) for CREATE TABLE) is still supported. While that requires a bit of support code, it seems unnecessary to break applications / dumps that do not use oids, and are explicit about not using them. The biggest user of WITH OID columns was postgres' catalog. This commit changes all 'magic' oid columns to be columns that are normally declared and stored. To reduce unnecessary query breakage all the newly added columns are still named 'oid', even if a table's column naming scheme would indicate 'reloid' or such. This obviously requires adapting a lot code, mostly replacing oid access via HeapTupleGetOid() with access to the underlying Form_pg_*->oid column. The bootstrap process now assigns oids for all oid columns in genbki.pl that do not have an explicit value (starting at the largest oid previously used), only oids assigned later by oids will be above FirstBootstrapObjectId. As the oid column now is a normal column the special bootstrap syntax for oids has been removed. Oids are not automatically assigned during insertion anymore, all backend code explicitly assigns oids with GetNewOidWithIndex(). For the rare case that insertions into the catalog via SQL are called for the new pg_nextoid() function can be used (which only works on catalog tables). The fact that oid columns on system tables are now normal columns means that they will be included in the set of columns expanded by * (i.e. SELECT * FROM pg_class will now include the table's oid, previously it did not). It'd not technically be hard to hide oid column by default, but that'd mean confusing behavior would either have to be carried forward forever, or it'd cause breakage down the line. While it's not unlikely that further adjustments are needed, the scope/invasiveness of the patch makes it worthwhile to get merge this now. It's painful to maintain externally, too complicated to commit after the code code freeze, and a dependency of a number of other patches. Catversion bump, for obvious reasons. Author: Andres Freund, with contributions by John Naylor Discussion: https://postgr.es/m/20180930034810.ywp2c7awz7opzcfr@alap3.anarazel.de
* Fix spelling errors and typos in commentsMagnus Hagander2018-11-02
| | | | Author: Daniel Gustafsson <daniel@yesql.se>
* Fix typo in commentMagnus Hagander2018-03-29
| | | | Arthur Zakirov, confirmed by Thomas Munro
* Make plpgsql use its DTYPE_REC code paths for composite-type variables.Tom Lane2018-02-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Formerly, DTYPE_REC was used only for variables declared as "record"; variables of named composite types used DTYPE_ROW, which is faster for some purposes but much less flexible. In particular, the ROW code paths are entirely incapable of dealing with DDL-caused changes to the number or data types of the columns of a row variable, once a particular plpgsql function has been parsed for the first time in a session. And, since the stored representation of a ROW isn't a tuple, there wasn't any easy way to deal with variables of domain-over-composite types, since the domain constraint checking code would expect the value to be checked to be a tuple. A lesser, but still real, annoyance is that ROW format cannot represent a true NULL composite value, only a row of per-field NULL values, which is not exactly the same thing. Hence, switch to using DTYPE_REC for all composite-typed variables, whether "record", named composite type, or domain over named composite type. DTYPE_ROW remains but is used only for its native purpose, to represent a fixed-at-compile-time list of variables, for instance the targets of an INTO clause. To accomplish this without taking significant performance losses, introduce infrastructure that allows storing composite-type variables as "expanded objects", similar to the "expanded array" infrastructure introduced in commit 1dc5ebc90. A composite variable's value is thereby kept (most of the time) in the form of separate Datums, so that field accesses and updates are not much more expensive than they were in the ROW format. This holds the line, more or less, on performance of variables of named composite types in field-access-intensive microbenchmarks, and makes variables declared "record" perform much better than before in similar tests. In addition, the logic involved with enforcing composite-domain constraints against updates of individual fields is in the expanded record infrastructure not plpgsql proper, so that it might be reusable for other purposes. In further support of this, introduce a typcache feature for assigning a unique-within-process identifier to each distinct tuple descriptor of interest; in particular, DDL alterations on composite types result in a new identifier for that type. This allows very cheap detection of the need to refresh tupdesc-dependent data. This improves on the "tupDescSeqNo" idea I had in commit 687f096ea: that assigned identifying sequence numbers to successive versions of individual composite types, but the numbers were not unique across different types, nor was there support for assigning numbers to registered record types. In passing, allow plpgsql functions to accept as well as return type "record". There was no good reason for the old restriction, and it was out of step with most of the other PLs. Tom Lane, reviewed by Pavel Stehule Discussion: https://postgr.es/m/8962.1514399547@sss.pgh.pa.us
* Update copyright for 2018Bruce Momjian2018-01-02
| | | | Backpatch-through: certain files through 9.3
* Make PL/Python handle domain-type conversions correctly.Tom Lane2017-11-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix PL/Python so that it can handle domains over composite, and so that it enforces domain constraints correctly in other cases that were not always done properly before. Notably, it didn't do arrays of domains right (oversight in commit c12d570fa), and it failed to enforce domain constraints when returning a composite type containing a domain field, and if a transform function is being used for a domain's base type then it failed to enforce domain constraints on the result. Also, in many places it missed checking domain constraints on null values, because the plpy_typeio code simply wasn't called for Py_None. Rather than try to band-aid these problems, I made a significant refactoring of the plpy_typeio logic. The existing design of recursing for array and composite members is extended to also treat domains as containers requiring recursion, and the APIs for the module are cleaned up and simplified. The patch also modifies plpy_typeio to rely on the typcache more than it did before (which was pretty much not at all). This reduces the need for repetitive lookups, and lets us get rid of an ad-hoc scheme for detecting changes in composite types. I added a couple of small features to typcache to help with that. Although some of this is fixing bugs that long predate v11, I don't think we should risk a back-patch: it's a significant amount of code churn, and there've been no complaints from the field about the bugs. Tom Lane, reviewed by Anthony Bykov Discussion: https://postgr.es/m/24449.1509393613@sss.pgh.pa.us
* Support domains over composite types.Tom Lane2017-10-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | This is the last major omission in our domains feature: you can now make a domain over anything that's not a pseudotype. The major complication from an implementation standpoint is that places that might be creating tuples of a domain type now need to be prepared to apply domain_check(). It seems better that unprepared code fail with an error like "<type> is not composite" than that it silently fail to apply domain constraints. Therefore, relevant infrastructure like get_func_result_type() and lookup_rowtype_tupdesc() has been adjusted to treat domain-over-composite as a distinct case that unprepared code won't recognize, rather than just transparently treating it the same as plain composite. This isn't a 100% solution to the possibility of overlooked domain checks, but it catches most places. In passing, improve typcache.c's support for domains (it can now cache the identity of a domain's base type), and rewrite the argument handling logic in jsonfuncs.c's populate_record[set]_worker to reduce duplicative per-call lookups. I believe this is code-complete so far as the core and contrib code go. The PLs need varying amounts of work, which will be tackled in followup patches. Discussion: https://postgr.es/m/4206.1499798337@sss.pgh.pa.us
* Fix typcache's failure to treat ranges as container types.Tom Lane2017-10-20
| | | | | | | | | | | | | | | | | Like the similar logic for arrays and records, it's necessary to examine the range's subtype to decide whether the range type can support hashing. We can omit checking the subtype for btree-defined operations, though, since range subtypes are required to have those operations. (Possibly that simplification for btree cases led us to overlook that it does not apply for hash cases.) This is only an issue if the subtype lacks hash support, which is not true of any built-in range type, but it's easy to demonstrate a problem with a range type over, eg, money: you can get a "could not identify a hash function" failure when the planner is misled into thinking that hash join or aggregation would work. This was born broken, so back-patch to all supported branches.
* Fix misimplementation of typcache logic for extended hashing.Tom Lane2017-10-20
| | | | | | | | | | | The previous coding would report that an array type supports extended hashing if its element type supports regular hashing. This bug is only latent at the moment, since AFAICS there is not yet any code that depends on checking presence of extended-hashing support to make any decisions. (And in any case it wouldn't matter unless the element type has only regular hashing, which isn't true of any core data type.) But that doesn't make it less broken. Extend the cache_array_element_properties infrastructure to check this properly.
* Fix bogus size calculation introduced by commit cc5f81366.Tom Lane2017-09-17
| | | | | | | | | The elements of RecordCacheArray are TupleDesc, not TupleDesc *. Those are actually the same size, so that this error is harmless, but it's still wrong --- and it might bite us someday, if TupleDesc ever became a struct, say. Per Coverity.
* Get rid of shared_record_typmod_registry_worker_detach; it doesn't work.Tom Lane2017-09-15
| | | | | | | | | | | | | | | | | This code is unsafe, as proven by buildfarm failures, because it tries to access shared memory that might already be gone. It's also unnecessary, because we're about to exit the process anyway and so the record type cache should never be accessed again. The idea was to lay some foundations for someday recycling workers --- which would require attaching to a different shared tupdesc registry --- but that will require considerably more thought. In the meantime let's save some bytes by just removing the nonfunctional code. Problem identification, and proposal to fix by removing functionality from the detach function, by Thomas Munro. I went a bit further by removing the function altogether. Discussion: https://postgr.es/m/E1dsguX-00056N-9x@gemulon.postgresql.org
* Don't use anonymous unions.Tom Lane2017-09-15
| | | | | | | | | Commit cc5f81366c36b3dd8f02bd9be1cf75b2cc8482bd introduced a language feature that is not acceptable to strict C89 compilers. Thomas Munro Per buildfarm.
* Add support for coordinating record typmods among parallel workers.Andres Freund2017-09-14
| | | | | | | | | | | | | | | | | | | | | | Tuples can have type RECORDOID and a typmod number that identifies a blessed TupleDesc in a backend-private cache. To support the sharing of such tuples through shared memory and temporary files, provide a typmod registry in shared memory. To achieve that, introduce per-session DSM segments, created on demand when a backend first runs a parallel query. The per-session DSM segment has a table-of-contents just like the per-query DSM segment, and initially the contents are a shared record typmod registry and a DSA area to provide the space it needs to grow. State relating to the current session is accessed via a Session object reached through global variable CurrentSession that may require significant redesign further down the road as we figure out what else needs to be shared or remodelled. Author: Thomas Munro Reviewed-By: Andres Freund Discussion: https://postgr.es/m/CAEepm=0ZtQ-SpsgCyzzYpsXS6e=kZWqk3g5Ygn3MDV7A8dabUA@mail.gmail.com
* Introduce 64-bit hash functions with a 64-bit seed.Robert Haas2017-08-31
| | | | | | | | | | | | | | | | This will be useful for hash partitioning, which needs a way to seed the hash functions to avoid problems such as a hash index on a hash partitioned table clumping all values into a small portion of the bucket space; it's also useful for anything that wants a 64-bit hash value rather than a 32-bit hash value. Just in case somebody wants a 64-bit hash value that is compatible with the existing 32-bit hash values, make the low 32-bits of the 64-bit hash value match the 32-bit hash value when the seed is 0. Robert Haas and Amul Sul Discussion: http://postgr.es/m/CA+Tgmoafx2yoJuhCQQOL5CocEi-w_uG4S2xT0EtgiJnPGcHW3g@mail.gmail.com
* Refactor typcache.c's record typmod hash table.Andres Freund2017-08-22
| | | | | | | | | | | | | | | | Previously, tuple descriptors were stored in chains keyed by a fixed size array of OIDs. That meant there were effectively two levels of collision chain -- one inside and one outside the hash table. Instead, let dynahash.c look after conflicts for us by supplying a proper hash and equal function pair. This is a nice cleanup on its own, but also simplifies followup changes allowing blessed TupleDescs to be shared between backends participating in parallel query. Author: Thomas Munro Reviewed-By: Andres Freund Discussion: https://postgr.es/m/CAEepm%3D34GVhOL%2BarUx56yx7OPk7%3DqpGsv3CpO54feqjAwQKm5g%40mail.gmail.com
* Change tupledesc->attrs[n] to TupleDescAttr(tupledesc, n).Andres Freund2017-08-20
| | | | | | | | | | | This is a mechanical change in preparation for a later commit that will change the layout of TupleDesc. Introducing a macro to abstract the details of where attributes are stored will allow us to change that in separate step and revise it in future. Author: Thomas Munro, editorialized by Andres Freund Reviewed-By: Andres Freund Discussion: https://postgr.es/m/CAEepm=0ZtQ-SpsgCyzzYpsXS6e=kZWqk3g5Ygn3MDV7A8dabUA@mail.gmail.com
* Phase 2 of pgindent updates.Tom Lane2017-06-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Change pg_bsd_indent to follow upstream rules for placement of comments to the right of code, and remove pgindent hack that caused comments following #endif to not obey the general rule. Commit e3860ffa4dd0dad0dd9eea4be9cc1412373a8c89 wasn't actually using the published version of pg_bsd_indent, but a hacked-up version that tried to minimize the amount of movement of comments to the right of code. The situation of interest is where such a comment has to be moved to the right of its default placement at column 33 because there's code there. BSD indent has always moved right in units of tab stops in such cases --- but in the previous incarnation, indent was working in 8-space tab stops, while now it knows we use 4-space tabs. So the net result is that in about half the cases, such comments are placed one tab stop left of before. This is better all around: it leaves more room on the line for comment text, and it means that in such cases the comment uniformly starts at the next 4-space tab stop after the code, rather than sometimes one and sometimes two tabs after. Also, ensure that comments following #endif are indented the same as comments following other preprocessor commands such as #else. That inconsistency turns out to have been self-inflicted damage from a poorly-thought-through post-indent "fixup" in pgindent. This patch is much less interesting than the first round of indent changes, but also bulkier, so I thought it best to separate the effects. Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
* Initial pgindent run with pg_bsd_indent version 2.0.Tom Lane2017-06-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The new indent version includes numerous fixes thanks to Piotr Stefaniak. The main changes visible in this commit are: * Nicer formatting of function-pointer declarations. * No longer unexpectedly removes spaces in expressions using casts, sizeof, or offsetof. * No longer wants to add a space in "struct structname *varname", as well as some similar cases for const- or volatile-qualified pointers. * Declarations using PG_USED_FOR_ASSERTS_ONLY are formatted more nicely. * Fixes bug where comments following declarations were sometimes placed with no space separating them from the code. * Fixes some odd decisions for comments following case labels. * Fixes some cases where comments following code were indented to less than the expected column 33. On the less good side, it now tends to put more whitespace around typedef names that are not listed in typedefs.list. This might encourage us to put more effort into typedef name collection; it's not really a bug in indent itself. There are more changes coming after this round, having to do with comment indentation and alignment of lines appearing within parentheses. I wanted to limit the size of the diffs to something that could be reviewed without one's eyes completely glazing over, so it seemed better to split up the changes as much as practical. Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
* Faster expression evaluation and targetlist projection.Andres Freund2017-03-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This replaces the old, recursive tree-walk based evaluation, with non-recursive, opcode dispatch based, expression evaluation. Projection is now implemented as part of expression evaluation. This both leads to significant performance improvements, and makes future just-in-time compilation of expressions easier. The speed gains primarily come from: - non-recursive implementation reduces stack usage / overhead - simple sub-expressions are implemented with a single jump, without function calls - sharing some state between different sub-expressions - reduced amount of indirect/hard to predict memory accesses by laying out operation metadata sequentially; including the avoidance of nearly all of the previously used linked lists - more code has been moved to expression initialization, avoiding constant re-checks at evaluation time Future just-in-time compilation (JIT) has become easier, as demonstrated by released patches intended to be merged in a later release, for primarily two reasons: Firstly, due to a stricter split between expression initialization and evaluation, less code has to be handled by the JIT. Secondly, due to the non-recursive nature of the generated "instructions", less performance-critical code-paths can easily be shared between interpreted and compiled evaluation. The new framework allows for significant future optimizations. E.g.: - basic infrastructure for to later reduce the per executor-startup overhead of expression evaluation, by caching state in prepared statements. That'd be helpful in OLTPish scenarios where initialization overhead is measurable. - optimizing the generated "code". A number of proposals for potential work has already been made. - optimizing the interpreter. Similarly a number of proposals have been made here too. The move of logic into the expression initialization step leads to some backward-incompatible changes: - Function permission checks are now done during expression initialization, whereas previously they were done during execution. In edge cases this can lead to errors being raised that previously wouldn't have been, e.g. a NULL array being coerced to a different array type previously didn't perform checks. - The set of domain constraints to be checked, is now evaluated once during expression initialization, previously it was re-built every time a domain check was evaluated. For normal queries this doesn't change much, but e.g. for plpgsql functions, which caches ExprStates, the old set could stick around longer. The behavior around might still change. Author: Andres Freund, with significant changes by Tom Lane, changes by Heikki Linnakangas Reviewed-By: Tom Lane, Heikki Linnakangas Discussion: https://postgr.es/m/20161206034955.bh33paeralxbtluv@alap3.anarazel.de
* Update copyright via script for 2017Bruce Momjian2017-01-03
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* 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>
* 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 JelĂ­nek, and rather heavily editorialized on by me.
* 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.
* Apply table and domain CHECK constraints in name order.Tom Lane2015-03-23
| | | | | | | | | | | | | | | | | | | | | | | | Previously, CHECK constraints of the same scope were checked in whatever order they happened to be read from pg_constraint. (Usually, but not reliably, this would be creation order for domain constraints and reverse creation order for table constraints, because of differing implementation details.) Nondeterministic results of this sort are problematic at least for testing purposes, and in discussion it was agreed to be a violation of the principle of least astonishment. Therefore, borrow the principle already established for triggers, and apply such checks in name order (using strcmp() sort rules). This lets users control the check order if they have a mind to. Domain CHECK constraints still follow the rule of checking lower nested domains' constraints first; the name sort only applies to multiple constraints attached to the same domain. In passing, I failed to resist the temptation to wordsmith a bit in create_domain.sgml. Apply to HEAD only, since this could result in a behavioral change in existing applications, and the potential regression test failures have not actually been observed in our buildfarm.
* Use the typcache to cache constraints for domain types.Tom Lane2015-03-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Previously, we cached domain constraints for the life of a query, or really for the life of the FmgrInfo struct that was used to invoke domain_in() or domain_check(). But plpgsql (and probably other places) are set up to cache such FmgrInfos for the whole lifespan of a session, which meant they could be enforcing really stale sets of constraints. On the other hand, searching pg_constraint once per query gets kind of expensive too: testing says that as much as half the runtime of a trivial query such as "SELECT 0::domaintype" went into that. To fix this, delegate the responsibility for tracking a domain's constraints to the typcache, which has the infrastructure needed to detect syscache invalidation events that signal possible changes. This not only removes unnecessary repeat reads of pg_constraint, but ensures that we never apply stale constraint data: whatever we use is the current data according to syscache rules. Unfortunately, the current configuration of the system catalogs means we have to flush cached domain-constraint data whenever either pg_type or pg_constraint changes, which happens rather a lot (eg, creation or deletion of a temp table will do it). It might be worth rearranging things to split pg_constraint into two catalogs, of which the domain constraint one would probably be very low-traffic. That's a job for another patch though, and in any case this patch should improve matters materially even with that handicap. This patch makes use of the recently-added memory context reset callback feature to manage the lifespan of domain constraint caches, so that we don't risk deleting a cache that might be in the midst of evaluation. Although this is a bug fix as well as a performance improvement, no back-patch. There haven't been many if any field complaints about stale domain constraint checks, so it doesn't seem worth taking the risk of modifying data structures as basic as MemoryContexts in back branches.
* Use FLEXIBLE_ARRAY_MEMBER in some more places.Tom Lane2015-02-20
| | | | | | Fix a batch of structs that are only visible within individual .c files. Michael Paquier
* Update copyright for 2015Bruce Momjian2015-01-06
| | | | Backpatch certain files through 9.0
* Improve hash_create's API for selecting simple-binary-key hash functions.Tom Lane2014-12-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Previously, if you wanted anything besides C-string hash keys, you had to specify a custom hashing function to hash_create(). Nearly all such callers were specifying tag_hash or oid_hash; which is tedious, and rather error-prone, since a caller could easily miss the opportunity to optimize by using hash_uint32 when appropriate. Replace this with a design whereby callers using simple binary-data keys just specify HASH_BLOBS and don't need to mess with specific support functions. hash_create() itself will take care of optimizing when the key size is four bytes. This nets out saving a few hundred bytes of code space, and offers a measurable performance improvement in tidbitmap.c (which was not exploiting the opportunity to use hash_uint32 for its 4-byte keys). There might be some wins elsewhere too, I didn't analyze closely. In future we could look into offering a similar optimized hashing function for 8-byte keys. Under this design that could be done in a centralized and machine-independent fashion, whereas getting it right for keys of platform-dependent sizes would've been notationally painful before. For the moment, the old way still works fine, so as not to break source code compatibility for loadable modules. Eventually we might want to remove tag_hash and friends from the exported API altogether, since there's no real need for them to be explicitly referenced from outside dynahash.c. Teodor Sigaev and Tom Lane
* Improve typcache: cache negative lookup results, add invalidation logic.Tom Lane2014-11-28
| | | | | | | | | | | | | | | | | | | | | | | | | | Previously, if the typcache had for example tried and failed to find a hash opclass for a given data type, it would nonetheless repeat the unsuccessful catalog lookup each time it was asked again. This can lead to a significant amount of useless bufmgr traffic, as in a recent report from Scott Marlowe. Like the catalog caches, typcache should be able to cache negative results. This patch arranges that by making use of separate flag bits to remember whether a particular item has been looked up, rather than treating a zero OID as an indicator that no lookup has been done. Also, install a credible invalidation mechanism, namely watching for inval events in pg_opclass. The sole advantage of the lack of negative caching was that the code would cope if operators or opclasses got added for a type mid-session; to preserve that behavior we have to be able to invalidate stale lookup results. Updates in pg_opclass should be pretty rare in production systems, so it seems sufficient to just invalidate all the dependent data whenever one happens. Adding proper invalidation also means that this code will now react sanely if an opclass is dropped mid-session. Arguably, that's a back-patchable bug fix, but in view of the lack of complaints from the field I'll refrain from back-patching. (Probably, in most cases where an opclass is dropped, the data type itself is dropped soon after, so that this misfeasance has no bad consequences.)
* pgindent run for 9.4Bruce Momjian2014-05-06
| | | | | This includes removing tabs after periods in C comments, which was applied to back branches, so this change should not effect backpatching.
* Update copyright for 2014Bruce Momjian2014-01-07
| | | | | Update all files in head, and files COPYRIGHT and legal.sgml in all back branches.
* Use an MVCC snapshot, rather than SnapshotNow, for catalog scans.Robert Haas2013-07-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | SnapshotNow scans have the undesirable property that, in the face of concurrent updates, the scan can fail to see either the old or the new versions of the row. In many cases, we work around this by requiring DDL operations to hold AccessExclusiveLock on the object being modified; in some cases, the existing locking is inadequate and random failures occur as a result. This commit doesn't change anything related to locking, but will hopefully pave the way to allowing lock strength reductions in the future. The major issue has held us back from making this change in the past is that taking an MVCC snapshot is significantly more expensive than using a static special snapshot such as SnapshotNow. However, testing of various worst-case scenarios reveals that this problem is not severe except under fairly extreme workloads. To mitigate those problems, we avoid retaking the MVCC snapshot for each new scan; instead, we take a new snapshot only when invalidation messages have been processed. The catcache machinery already requires that invalidation messages be sent before releasing the related heavyweight lock; else other backends might rely on locally-cached data rather than scanning the catalog at all. Thus, making snapshot reuse dependent on the same guarantees shouldn't break anything that wasn't already subtly broken. Patch by me. Review by Michael Paquier and Andres Freund.
* Fix cache flush hazard in cache_record_field_properties().Tom Lane2013-06-11
| | | | | | | | | | | | We need to increment the refcount on the composite type's cached tuple descriptor while we do lookups of its column types. Otherwise a cache flush could occur and release the tuple descriptor before we're done with it. This fails reliably with -DCLOBBER_CACHE_ALWAYS, but the odds of a failure in a production build seem rather low (since the pfree'd descriptor typically wouldn't get scribbled on immediately). That may explain the lack of any previous reports. Buildfarm issue noted by Christian Ullrich. Back-patch to 9.1 where the bogus code was added.
* Update copyrights for 2013Bruce Momjian2013-01-01
| | | | | Fully update git head, and update back branches in ./COPYRIGHT and legal.sgml files.
* 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 resowner.hAlvaro Herrera2012-08-28
| | | | | This lets files that are mere users of ResourceOwner not automatically include the headers for stuff that is managed by the resowner mechanism.