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* Update copyright for 2019Bruce Momjian2019-01-02
| | | | Backpatch-through: certain files through 9.4
* 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
* Introduce notion of different types of slots (without implementing them).Andres Freund2018-11-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Upcoming work intends to allow pluggable ways to introduce new ways of storing table data. Accessing those table access methods from the executor requires TupleTableSlots to be carry tuples in the native format of such storage methods; otherwise there'll be a significant conversion overhead. Different access methods will require different data to store tuples efficiently (just like virtual, minimal, heap already require fields in TupleTableSlot). To allow that without requiring additional pointer indirections, we want to have different structs (embedding TupleTableSlot) for different types of slots. Thus different types of slots are needed, which requires adapting creators of slots. The slot that most efficiently can represent a type of tuple in an executor node will often depend on the type of slot a child node uses. Therefore we need to track the type of slot is returned by nodes, so parent slots can create slots based on that. Relatedly, JIT compilation of tuple deforming needs to know which type of slot a certain expression refers to, so it can create an appropriate deforming function for the type of tuple in the slot. But not all nodes will only return one type of slot, e.g. an append node will potentially return different types of slots for each of its subplans. Therefore add function that allows to query the type of a node's result slot, and whether it'll always be the same type (whether it's fixed). This can be queried using ExecGetResultSlotOps(). The scan, result, inner, outer type of slots are automatically inferred from ExecInitScanTupleSlot(), ExecInitResultSlot(), left/right subtrees respectively. If that's not correct for a node, that can be overwritten using new fields in PlanState. This commit does not introduce the actually abstracted implementation of different kind of TupleTableSlots, that will be left for a followup commit. The different types of slots introduced will, for now, still use the same backing implementation. While this already partially invalidates the big comment in tuptable.h, it seems to make more sense to update it later, when the different TupleTableSlot implementations actually exist. Author: Ashutosh Bapat and Andres Freund, with changes by Amit Khandekar Discussion: https://postgr.es/m/20181105210039.hh4vvi4vwoq5ba2q@alap3.anarazel.de
* Rejigger materializing and fetching a HeapTuple from a slot.Andres Freund2018-11-15
| | | | | | | | | | | | | | | | | | | | | | | | | Previously materializing a slot always returned a HeapTuple. As current work aims to reduce the reliance on HeapTuples (so other storage systems can work efficiently), that needs to change. Thus split the tasks of materializing a slot (i.e. making it independent from the underlying storage / other memory contexts) from fetching a HeapTuple from the slot. For brevity, allow to fetch a HeapTuple from a slot and materializing the slot at the same time, controlled by a parameter. For now some callers of ExecFetchSlotHeapTuple, with materialize = true, expect that changes to the heap tuple will be reflected in the underlying slot. Those places will be adapted in due course, so while not pretty, that's OK for now. Also rename ExecFetchSlotTuple to ExecFetchSlotHeapTupleDatum and ExecFetchSlotTupleDatum to ExecFetchSlotHeapTupleDatum, as it's likely that future storage methods will need similar methods. There already is ExecFetchSlotMinimalTuple, so the new names make the naming scheme more coherent. Author: Ashutosh Bapat and Andres Freund, with changes by Amit Khandekar Discussion: https://postgr.es/m/20181105210039.hh4vvi4vwoq5ba2q@alap3.anarazel.de
* Allow memory contexts to have both fixed and variable ident strings.Tom Lane2018-03-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Originally, we treated memory context names as potentially variable in all cases, and therefore always copied them into the context header. Commit 9fa6f00b1 rethought this a little bit and invented a distinction between fixed and variable names, skipping the copy step for the former. But we can make things both simpler and more useful by instead allowing there to be two parts to a context's identification, a fixed "name" and an optional, variable "ident". The name supplied in the context create call is now required to be a compile-time-constant string in all cases, as it is never copied but just pointed to. The "ident" string, if wanted, is supplied later. This is needed because typically we want the ident to be stored inside the context so that it's cleaned up automatically on context deletion; that means it has to be copied into the context before we can set the pointer. The cost of this approach is basically just an additional pointer field in struct MemoryContextData, which isn't much overhead, and is bought back entirely in the AllocSet case by not needing a headerSize field anymore, since we no longer have to cope with variable header length. In addition, we can simplify the internal interfaces for memory context creation still further, saving a few cycles there. And it's no longer true that a custom identifier disqualifies a context from participating in aset.c's freelist scheme, so possibly there's some win on that end. All the places that were using non-compile-time-constant context names are adjusted to put the variable info into the "ident" instead. This allows more effective identification of those contexts in many cases; for example, subsidary contexts of relcache entries are now identified by both type (e.g. "index info") and relname, where before you got only one or the other. Contexts associated with PL function cache entries are now identified more fully and uniformly, too. I also arranged for plancache contexts to use the query source string as their identifier. This is basically free for CachedPlanSources, as they contained a copy of that string already. We pay an extra pstrdup to do it for CachedPlans. That could perhaps be avoided, but it would make things more fragile (since the CachedPlanSource is sometimes destroyed first). I suspect future improvements in error reporting will require CachedPlans to have a copy of that string anyway, so it's not clear that it's worth moving mountains to avoid it now. This also changes the APIs for context statistics routines so that the context-specific routines no longer assume that output goes straight to stderr, nor do they know all details of the output format. This is useful immediately to reduce code duplication, and it also allows for external code to do something with stats output that's different from printing to stderr. The reason for pushing this now rather than waiting for v12 is that it rethinks some of the API changes made by commit 9fa6f00b1. Seems better for extension authors to endure just one round of API changes not two. Discussion: https://postgr.es/m/CAB=Je-FdtmFZ9y9REHD7VsSrnCkiBhsA4mdsLKSPauwXtQBeNA@mail.gmail.com
* Support INOUT arguments in proceduresPeter Eisentraut2018-03-14
| | | | | | | | | | In a top-level CALL, the values of INOUT arguments will be returned as a result row. In PL/pgSQL, the values are assigned back to the input arguments. In other languages, the same convention as for return a record from a function is used. That does not require any code changes in the PL implementations. Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com>
* Add prokind column, replacing proisagg and proiswindowPeter Eisentraut2018-03-02
| | | | | | | | | | The new column distinguishes normal functions, procedures, aggregates, and window functions. This replaces the existing columns proisagg and proiswindow, and replaces the convention that procedures are indicated by prorettype == 0. Also change prorettype to be VOIDOID for procedures. Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: Michael Paquier <michael@paquier.xyz>
* Update copyright for 2018Bruce Momjian2018-01-02
| | | | Backpatch-through: certain files through 9.3
* Rearrange execution of PARAM_EXTERN Params for plpgsql's benefit.Tom Lane2017-12-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch does three interrelated things: * Create a new expression execution step type EEOP_PARAM_CALLBACK and add the infrastructure needed for add-on modules to generate that. As discussed, the best control mechanism for that seems to be to add another hook function to ParamListInfo, which will be called by ExecInitExpr if it's supplied and a PARAM_EXTERN Param is found. For stand-alone expressions, we add a new entry point to allow the ParamListInfo to be specified directly, since it can't be retrieved from the parent plan node's EState. * Redesign the API for the ParamListInfo paramFetch hook so that the ParamExternData array can be entirely virtual. This also lets us get rid of ParamListInfo.paramMask, instead leaving it to the paramFetch hook to decide which param IDs should be accessible or not. plpgsql_param_fetch was already doing the identical masking check, so having callers do it too seemed redundant. While I was at it, I added a "speculative" flag to paramFetch that the planner can specify as TRUE to avoid unwanted failures. This solves an ancient problem for plpgsql that it couldn't provide values of non-DTYPE_VAR variables to the planner for fear of triggering premature "record not assigned yet" or "field not found" errors during planning. * Rework plpgsql to get rid of the need for "unshared" parameter lists, by dint of turning the single ParamListInfo per estate into a nearly read-only data structure that doesn't instantiate any per-variable data. Instead, the paramFetch hook controls access to per-variable data and can make the right decisions on the fly, replacing the cases that we used to need multiple ParamListInfos for. This might perhaps have been a performance loss on its own, but by using a paramCompile hook we can bypass plpgsql_param_fetch entirely during normal query execution. (It's now only called when, eg, we copy the ParamListInfo into a cursor portal. copyParamList() or SerializeParamList() effectively instantiate the virtual parameter array as a simple physical array without a paramFetch hook, which is what we want in those cases.) This allows reverting most of commit 6c82d8d1f, though I kept the cosmetic code-consolidation aspects of that (eg the assign_simple_var function). Performance testing shows this to be at worst a break-even change, and it can provide wins ranging up to 20% in test cases involving accesses to fields of "record" variables. The fact that values of such variables can now be exposed to the planner might produce wins in some situations, too, but I've not pursued that angle. In passing, remove the "parent" pointer from the arguments to ExecInitExprRec and related functions, instead storing that pointer in a transient field in ExprState. The ParamListInfo pointer for a stand-alone expression is handled the same way; we'd otherwise have had to add yet another recursively-passed-down argument in expression compilation. Discussion: https://postgr.es/m/32589.1513706441@sss.pgh.pa.us
* SQL proceduresPeter Eisentraut2017-11-30
| | | | | | | | | | | | | | | | | | | | | This adds a new object type "procedure" that is similar to a function but does not have a return type and is invoked by the new CALL statement instead of SELECT or similar. This implementation is aligned with the SQL standard and compatible with or similar to other SQL implementations. This commit adds new commands CALL, CREATE/ALTER/DROP PROCEDURE, as well as ALTER/DROP ROUTINE that can refer to either a function or a procedure (or an aggregate function, as an extension to SQL). There is also support for procedures in various utility commands such as COMMENT and GRANT, as well as support in pg_dump and psql. Support for defining procedures is available in all the languages supplied by the core distribution. While this commit is mainly syntax sugar around existing functionality, future features will rely on having procedures as a separate object type. Reviewed-by: Andrew Dunstan <andrew.dunstan@2ndquadrant.com>
* 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
* Reduce excessive dereferencing of function pointersPeter Eisentraut2017-09-07
| | | | | | | | | | | | It is equivalent in ANSI C to write (*funcptr) () and funcptr(). These two styles have been applied inconsistently. After discussion, we'll use the more verbose style for plain function pointer variables, to make it clear that it's a variable, and the shorter style when the function pointer is in a struct (s.func() or s->func()), because then it's clear that it's not a plain function name, and otherwise the excessive punctuation makes some of those invocations hard to read. Discussion: https://www.postgresql.org/message-id/f52c16db-14ed-757d-4b48-7ef360b1631d@2ndquadrant.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 3 of pgindent updates.Tom Lane2017-06-21
| | | | | | | | | | | | | | | | | | | | | | | | | Don't move parenthesized lines to the left, even if that means they flow past the right margin. By default, BSD indent lines up statement continuation lines that are within parentheses so that they start just to the right of the preceding left parenthesis. However, traditionally, if that resulted in the continuation line extending to the right of the desired right margin, then indent would push it left just far enough to not overrun the margin, if it could do so without making the continuation line start to the left of the current statement indent. That makes for a weird mix of indentations unless one has been completely rigid about never violating the 80-column limit. This behavior has been pretty universally panned by Postgres developers. Hence, disable it with indent's new -lpl switch, so that parenthesized lines are always lined up with the preceding left paren. This patch is much less interesting than the first round of indent changes, but also bulkier, so I thought it best to separate the effects. Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
* 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
* Disallow set-returning functions inside CASE or COALESCE.Tom Lane2017-06-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When we reimplemented SRFs in commit 69f4b9c85, our initial choice was to allow the behavior to vary from historical practice in cases where a SRF call appeared within a conditional-execution construct (currently, only CASE or COALESCE). But that was controversial to begin with, and subsequent discussion has resulted in a consensus that it's better to throw an error instead of executing the query differently from before, so long as we can provide a reasonably clear error message and a way to rewrite the query. Hence, add a parser mechanism to allow detection of such cases during parse analysis. The mechanism just requires storing, in the ParseState, a pointer to the set-returning FuncExpr or OpExpr most recently emitted by parse analysis. Then the parsing functions for CASE and COALESCE can detect the presence of a SRF in their arguments by noting whether this pointer changes while analyzing their arguments. Furthermore, if it does, it provides a suitable error cursor location for the complaint. (This means that if there's more than one SRF in the arguments, the error will point at the last one to be analyzed not the first. While connoisseurs of parsing behavior might find that odd, it's unlikely the average user would ever notice.) While at it, we can also provide more specific error messages than before about some pre-existing restrictions, such as no-SRFs-within-aggregates. Also, reject at parse time cases where a NULLIF or IS DISTINCT FROM construct would need to return a set. We've never supported that, but the restriction is depended on in more subtle ways now, so it seems wise to detect it at the start. Also, provide some documentation about how to rewrite a SRF-within-CASE query using a custom wrapper SRF. It turns out that the information_schema.user_mapping_options view contained an instance of exactly the behavior we're now forbidding; but rewriting it makes it more clear and safer too. initdb forced because of user_mapping_options change. Patch by me, with error message suggestions from Alvaro Herrera and Andres Freund, pursuant to a complaint from Regina Obe. Discussion: https://postgr.es/m/000001d2d5de$d8d66170$8a832450$@pcorp.us
* Improve castNode notation by introducing list-extraction-specific variants.Tom Lane2017-04-10
| | | | | | | | | | | | | | | | | This extends the castNode() notation introduced by commit 5bcab1114 to provide, in one step, extraction of a list cell's pointer and coercion to a concrete node type. For example, "lfirst_node(Foo, lc)" is the same as "castNode(Foo, lfirst(lc))". Almost half of the uses of castNode that have appeared so far include a list extraction call, so this is pretty widely useful, and it saves a few more keystrokes compared to the old way. As with the previous patch, back-patch the addition of these macros to pg_list.h, so that the notation will be available when back-patching. Patch by me, after an idea of Andrew Gierth's. Discussion: https://postgr.es/m/14197.1491841216@sss.pgh.pa.us
* Add infrastructure to support EphemeralNamedRelation references.Kevin Grittner2017-03-31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A QueryEnvironment concept is added, which allows new types of objects to be passed into queries from parsing on through execution. At this point, the only thing implemented is a collection of EphemeralNamedRelation objects -- relations which can be referenced by name in queries, but do not exist in the catalogs. The only type of ENR implemented is NamedTuplestore, but provision is made to add more types fairly easily. An ENR can carry its own TupleDesc or reference a relation in the catalogs by relid. Although these features can be used without SPI, convenience functions are added to SPI so that ENRs can easily be used by code run through SPI. The initial use of all this is going to be transition tables in AFTER triggers, but that will be added to each PL as a separate commit. An incidental effect of this patch is to produce a more informative error message if an attempt is made to modify the contents of a CTE from a referencing DML statement. No tests previously covered that possibility, so one is added. Kevin Grittner and Thomas Munro Reviewed by Heikki Linnakangas, David Fetter, and Thomas Munro with valuable comments and suggestions from many others
* 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
* Improve access to parallel query from procedural languages.Robert Haas2017-03-24
| | | | | | | | | | | | | | | | | | | | | | | | | In SQL, the ability to use parallel query was previous contingent on fcache->readonly_func, which is only set for non-volatile functions; but the volatility of a function has no bearing on whether queries inside it can use parallelism. Remove that condition. SPI_execute and SPI_execute_with_args always run the plan just once, though not necessarily to completion. Given the changes in commit 691b8d59281b5177f16fe80858df921f77a8e955, it's sensible to pass CURSOR_OPT_PARALLEL_OK here, so do that. This improves access to parallelism for any caller that uses these functions to execute queries. Such callers include plperl, plpython, pltcl, and plpgsql, though it's not the case that they all use these functions exclusively. In plpgsql, allow parallel query for plain SELECT queries (as opposed to PERFORM, which already worked) and for plain expressions (which probably won't go through the executor at all, because they will likely be simple expressions, but if they do then this helps). Rafia Sabih and Robert Haas, reviewed by Dilip Kumar and Amit Kapila Discussion: http://postgr.es/m/CAOGQiiMfJ+4SQwgG=6CVHWoisiU0+7jtXSuiyXBM3y=A=eJzmg@mail.gmail.com
* Allow for parallel execution whenever ExecutorRun() is done only once.Robert Haas2017-03-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Previously, it was unsafe to execute a plan in parallel if ExecutorRun() might be called with a non-zero row count. However, it's quite easy to fix things up so that we can support that case, provided that it is known that we will never call ExecutorRun() a second time for the same QueryDesc. Add infrastructure to signal this, and cross-checks to make sure that a caller who claims this is true doesn't later reneg. While that pattern never happens with queries received directly from a client -- there's no way to know whether multiple Execute messages will be sent unless the first one requests all the rows -- it's pretty common for queries originating from procedural languages, which often limit the result to a single tuple or to a user-specified number of tuples. This commit doesn't actually enable parallelism in any additional cases, because currently none of the places that would be able to benefit from this infrastructure pass CURSOR_OPT_PARALLEL_OK in the first place, but it makes it much more palatable to pass CURSOR_OPT_PARALLEL_OK in places where we currently don't, because it eliminates some cases where we'd end up having to run the parallel plan serially. Patch by me, based on some ideas from Rafia Sabih and corrected by Rafia Sabih based on feedback from Dilip Kumar and myself. Discussion: http://postgr.es/m/CA+TgmobXEhvHbJtWDuPZM9bVSLiTj-kShxQJ2uM5GPDze9fRYA@mail.gmail.com
* Use castNode() in a bunch of statement-list-related code.Tom Lane2017-01-26
| | | | | | | | | | | | | When I wrote commit ab1f0c822, I really missed the castNode() macro that Peter E. had proposed shortly before. This back-fills the uses I would have put it to. It's probably not all that significant, but there are more assertions here than there were before, and conceivably they will help catch any bugs associated with those representation changes. I left behind a number of usages like "(Query *) copyObject(query_var)". Those could have been converted as well, but Peter has proposed another notational improvement that would handle copyObject cases automatically, so I let that be for now.
* Use the new castNode() macro in a number of places.Andres Freund2017-01-26
| | | | | | | | | This is far from a pervasive conversion, but it's a good starting point. Author: Peter Eisentraut, with some minor changes by me Reviewed-By: Tom Lane Discussion: https://postgr.es/m/c5d387d9-3440-f5e0-f9d4-71d53b9fbe52@2ndquadrant.com
* Change representation of statement lists, and add statement location info.Tom Lane2017-01-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch makes several changes that improve the consistency of representation of lists of statements. It's always been the case that the output of parse analysis is a list of Query nodes, whatever the types of the individual statements in the list. This patch brings similar consistency to the outputs of raw parsing and planning steps: * The output of raw parsing is now always a list of RawStmt nodes; the statement-type-dependent nodes are one level down from that. * The output of pg_plan_queries() is now always a list of PlannedStmt nodes, even for utility statements. In the case of a utility statement, "planning" just consists of wrapping a CMD_UTILITY PlannedStmt around the utility node. This list representation is now used in Portal and CachedPlan plan lists, replacing the former convention of intermixing PlannedStmts with bare utility-statement nodes. Now, every list of statements has a consistent head-node type depending on how far along it is in processing. This allows changing many places that formerly used generic "Node *" pointers to use a more specific pointer type, thus reducing the number of IsA() tests and casts needed, as well as improving code clarity. Also, the post-parse-analysis representation of DECLARE CURSOR is changed so that it looks more like EXPLAIN, PREPARE, etc. That is, the contained SELECT remains a child of the DeclareCursorStmt rather than getting flipped around to be the other way. It's now true for both Query and PlannedStmt that utilityStmt is non-null if and only if commandType is CMD_UTILITY. That allows simplifying a lot of places that were testing both fields. (I think some of those were just defensive programming, but in many places, it was actually necessary to avoid confusing DECLARE CURSOR with SELECT.) Because PlannedStmt carries a canSetTag field, we're also able to get rid of some ad-hoc rules about how to reconstruct canSetTag for a bare utility statement; specifically, the assumption that a utility is canSetTag if and only if it's the only one in its list. While I see no near-term need for relaxing that restriction, it's nice to get rid of the ad-hocery. The API of ProcessUtility() is changed so that what it's passed is the wrapper PlannedStmt not just the bare utility statement. This will affect all users of ProcessUtility_hook, but the changes are pretty trivial; see the affected contrib modules for examples of the minimum change needed. (Most compilers should give pointer-type-mismatch warnings for uncorrected code.) There's also a change in the API of ExplainOneQuery_hook, to pass through cursorOptions instead of expecting hook functions to know what to pick. This is needed because of the DECLARE CURSOR changes, but really should have been done in 9.6; it's unlikely that any extant hook functions know about using CURSOR_OPT_PARALLEL_OK. Finally, teach gram.y to save statement boundary locations in RawStmt nodes, and pass those through to Query and PlannedStmt nodes. This allows more intelligent handling of cases where a source query string contains multiple statements. This patch doesn't actually do anything with the information, but a follow-on patch will. (Passing this information through cleanly is the true motivation for these changes; while I think this is all good cleanup, it's unlikely we'd have bothered without this end goal.) catversion bump because addition of location fields to struct Query affects stored rules. This patch is by me, but it owes a good deal to Fabien Coelho who did a lot of preliminary work on the problem, and also reviewed the patch. Discussion: https://postgr.es/m/alpine.DEB.2.20.1612200926310.29821@lancre
* Throw suitable error for COPY TO STDOUT/FROM STDIN in a SQL function.Tom Lane2017-01-14
| | | | | | | | | | | | | | | | | A client copy can't work inside a function because the FE/BE wire protocol doesn't support nesting of a COPY operation within query results. (Maybe it could, but the protocol spec doesn't suggest that clients should support this, and libpq for one certainly doesn't.) In most PLs, this prohibition is enforced by spi.c, but SQL functions don't use SPI. A comparison of _SPI_execute_plan() and init_execution_state() shows that rejecting client COPY is the only discrepancy in what they allow, so there's no other similar bugs. This is an astonishingly ancient oversight, so back-patch to all supported branches. Report: https://postgr.es/m/BY2PR05MB2309EABA3DEFA0143F50F0D593780@BY2PR05MB2309.namprd05.prod.outlook.com
* Update copyright via script for 2017Bruce Momjian2017-01-03
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* 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>
* pgindent run for 9.6Robert Haas2016-06-09
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* Stop the executor if no more tuples can be sent from worker to leader.Robert Haas2016-06-06
| | | | | | | | | | | | | | | | | | | | | If a Gather node has read as many tuples as it needs (for example, due to Limit) it may detach the queue connecting it to the worker before reading all of the worker's tuples. Rather than let the worker continue to generate and send all of the results, have it stop after sending the next tuple. More could be done here to stop the worker even quicker, but this is about as well as we can hope to do for 9.6. This is in response to a problem report from Andreas Seltenreich. Commit 44339b892a04e94bbb472235882dc6f7023bdc65 should be actually be sufficient to fix that example even without this change, but it seems better to do this, too, since we might otherwise waste quite a large amount of effort in one or more workers. Discussion: CAA4eK1KOKGqmz9bGu+Z42qhRwMbm4R5rfnqsLCNqFs9j14jzEA@mail.gmail.com Amit Kapila
* Widen query numbers-of-tuples-processed counters to uint64.Tom Lane2016-03-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | This patch widens SPI_processed, EState's es_processed field, PortalData's portalPos field, FuncCallContext's call_cntr and max_calls fields, ExecutorRun's count argument, PortalRunFetch's result, and the max number of rows in a SPITupleTable to uint64, and deals with (I hope) all the ensuing fallout. Some of these values were declared uint32 before, and others "long". I also removed PortalData's posOverflow field, since that logic seems pretty useless given that portalPos is now always 64 bits. The user-visible results are that command tags for SELECT etc will correctly report tuple counts larger than 4G, as will plpgsql's GET GET DIAGNOSTICS ... ROW_COUNT command. Queries processing more tuples than that are still not exactly the norm, but they're becoming more common. Most values associated with FETCH/MOVE distances, such as PortalRun's count argument and the count argument of most SPI functions that have one, remain declared as "long". It's not clear whether it would be worth promoting those to int64; but it would definitely be a large dollop of additional API churn on top of this, and it would only help 32-bit platforms which seem relatively less likely to see any benefit. Andreas Scherbaum, reviewed by Christian Ullrich, additional hacking by me
* Update copyright for 2016Bruce Momjian2016-01-02
| | | | Backpatch certain files through 9.1
* Fix problems with ParamListInfo serialization mechanism.Robert Haas2015-11-02
| | | | | | | | | | | | | | | | | | | | | | Commit d1b7c1ffe72e86932b5395f29e006c3f503bc53d introduced a mechanism for serializing a ParamListInfo structure to be passed to a parallel worker. However, this mechanism failed to handle external expanded values, as pointed out by Noah Misch. Repair. Moreover, plpgsql_param_fetch requires adjustment because the serialization mechanism needs it to skip evaluating unused parameters just as we would do when it is called from copyParamList, but params == estate->paramLI in that case. To fix, make the bms_is_member test in that function unconditional. Finally, have setup_param_list set a new ParamListInfo field, paramMask, to the parameters actually used in the expression, so that we don't try to fetch those that are not needed when serializing a parameter list. This isn't necessary for correctness, but it makes the performance of the parallel executor code comparable to what we do for cases involving cursors. Design suggestions and extensive review by Noah Misch. Patch by me.
* Determine whether it's safe to attempt a parallel plan for a query.Robert Haas2015-09-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 924bcf4f16d54c55310b28f77686608684734f42 introduced a framework for parallel computation in PostgreSQL that makes most but not all built-in functions safe to execute in parallel mode. In order to have parallel query, we'll need to be able to determine whether that query contains functions (either built-in or user-defined) that cannot be safely executed in parallel mode. This requires those functions to be labeled, so this patch introduces an infrastructure for that. Some functions currently labeled as safe may need to be revised depending on how pending issues related to heavyweight locking under paralllelism are resolved. Parallel plans can't be used except for the case where the query will run to completion. If portal execution were suspended, the parallel mode restrictions would need to remain in effect during that time, but that might make other queries fail. Therefore, this patch introduces a framework that enables consideration of parallel plans only when it is known that the plan will be run to completion. This probably needs some refinement; for example, at bind time, we do not know whether a query run via the extended protocol will be execution to completion or run with a limited fetch count. Having the client indicate its intentions at bind time would constitute a wire protocol break. Some contexts in which parallel mode would be safe are not adjusted by this patch; the default is not to try parallel plans except from call sites that have been updated to say that such plans are OK. This commit doesn't introduce any parallel paths or plans; it just provides a way to determine whether they could potentially be used. I'm committing it on the theory that the remaining parallel sequential scan patches will also get committed to this release, hopefully in the not-too-distant future. Robert Haas and Amit Kapila. Reviewed (in earlier versions) by Noah Misch.
* Create an infrastructure for parallel computation in PostgreSQL.Robert Haas2015-04-30
| | | | | | | | | | | | | | | | | This does four basic things. First, it provides convenience routines to coordinate the startup and shutdown of parallel workers. Second, it synchronizes various pieces of state (e.g. GUCs, combo CID mappings, transaction snapshot) from the parallel group leader to the worker processes. Third, it prohibits various operations that would result in unsafe changes to that state while parallelism is active. Finally, it propagates events that would result in an ErrorResponse, NoticeResponse, or NotifyResponse message being sent to the client from the parallel workers back to the master, from which they can then be sent on to the client. Robert Haas, Amit Kapila, Noah Misch, Rushabh Lathia, Jeevan Chalke. Suggestions and review from Andres Freund, Heikki Linnakangas, Noah Misch, Simon Riggs, Euler Taveira, and Jim Nasby.
* Use FLEXIBLE_ARRAY_MEMBER in a bunch more places.Tom Lane2015-02-20
| | | | | | | | | | | | | | | | Replace some bogus "x[1]" declarations with "x[FLEXIBLE_ARRAY_MEMBER]". Aside from being more self-documenting, this should help prevent bogus warnings from static code analyzers and perhaps compiler misoptimizations. This patch is just a down payment on eliminating the whole problem, but it gets rid of a lot of easy-to-fix cases. Note that the main problem with doing this is that one must no longer rely on computing sizeof(the containing struct), since the result would be compiler-dependent. Instead use offsetof(struct, lastfield). Autoconf also warns against spelling that offsetof(struct, lastfield[0]). Michael Paquier, review and additional fixes by me.
* Update copyright for 2015Bruce Momjian2015-01-06
| | | | Backpatch certain files through 9.0
* 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.
* Fix failure to detoast fields in composite elements of structured types.Tom Lane2014-05-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we have an array of records stored on disk, the individual record fields cannot contain out-of-line TOAST pointers: the tuptoaster.c mechanisms are only prepared to deal with TOAST pointers appearing in top-level fields of a stored row. The same applies for ranges over composite types, nested composites, etc. However, the existing code only took care of expanding sub-field TOAST pointers for the case of nested composites, not for other structured types containing composites. For example, given a command such as UPDATE tab SET arraycol = ARRAY[(ROW(x,42)::mycompositetype] ... where x is a direct reference to a field of an on-disk tuple, if that field is long enough to be toasted out-of-line then the TOAST pointer would be inserted as-is into the array column. If the source record for x is later deleted, the array field value would become a dangling pointer, leading to errors along the line of "missing chunk number 0 for toast value ..." when the value is referenced. A reproducible test case for this was provided by Jan Pecek, but it seems likely that some of the "missing chunk number" reports we've heard in the past were caused by similar issues. Code-wise, the problem is that PG_DETOAST_DATUM() is not adequate to produce a self-contained Datum value if the Datum is of composite type. Seen in this light, the problem is not just confined to arrays and ranges, but could also affect some other places where detoasting is done in that way, for example form_index_tuple(). I tried teaching the array code to apply toast_flatten_tuple_attribute() along with PG_DETOAST_DATUM() when the array element type is composite, but this was messy and imposed extra cache lookup costs whether or not any TOAST pointers were present, indeed sometimes when the array element type isn't even composite (since sometimes it takes a typcache lookup to find that out). The idea of extending that approach to all the places that currently use PG_DETOAST_DATUM() wasn't attractive at all. This patch instead solves the problem by decreeing that composite Datum values must not contain any out-of-line TOAST pointers in the first place; that is, we expand out-of-line fields at the point of constructing a composite Datum, not at the point where we're about to insert it into a larger tuple. This rule is applied only to true composite Datums, not to tuples that are being passed around the system as tuples, so it's not as invasive as it might sound at first. With this approach, the amount of code that has to be touched for a full solution is greatly reduced, and added cache lookup costs are avoided except when there actually is a TOAST pointer that needs to be inlined. The main drawback of this approach is that we might sometimes dereference a TOAST pointer that will never actually be used by the query, imposing a rather large cost that wasn't there before. On the other side of the coin, if the field value is used multiple times then we'll come out ahead by avoiding repeat detoastings. Experimentation suggests that common SQL coding patterns are unaffected either way, though. Applications that are very negatively affected could be advised to modify their code to not fetch columns they won't be using. In future, we might consider reverting this solution in favor of detoasting only at the point where data is about to be stored to disk, using some method that can drill down into multiple levels of nested structured types. That will require defining new APIs for structured types, though, so it doesn't seem feasible as a back-patchable fix. Note that this patch changes HeapTupleGetDatum() from a macro to a function call; this means that any third-party code using that macro will not get protection against creating TOAST-pointer-containing Datums until it's recompiled. The same applies to any uses of PG_RETURN_HEAPTUPLEHEADER(). It seems likely that this is not a big problem in practice: most of the tuple-returning functions in core and contrib produce outputs that could not possibly be toasted anyway, and the same probably holds for third-party extensions. This bug has existed since TOAST was invented, so back-patch to all supported branches.
* Fix *-qualification of named parameters in SQL-language functions.Tom Lane2014-02-03
| | | | | | | Given a composite-type parameter named x, "$1.*" worked fine, but "x.*" not so much. This has been broken since named parameter references were added in commit 9bff0780cf5be2193a5bad0d3df2dbe143085264, so patch back to 9.2. Per bug #9085 from Hardy Falk.
* Update copyright for 2014Bruce Momjian2014-01-07
| | | | | Update all files in head, and files COPYRIGHT and legal.sgml in all back branches.
* Support ordered-set (WITHIN GROUP) aggregates.Tom Lane2013-12-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduces generic support for ordered-set and hypothetical-set aggregate functions, as well as implementations of the instances defined in SQL:2008 (percentile_cont(), percentile_disc(), rank(), dense_rank(), percent_rank(), cume_dist()). We also added mode() though it is not in the spec, as well as versions of percentile_cont() and percentile_disc() that can compute multiple percentile values in one pass over the data. Unlike the original submission, this patch puts full control of the sorting process in the hands of the aggregate's support functions. To allow the support functions to find out how they're supposed to sort, a new API function AggGetAggref() is added to nodeAgg.c. This allows retrieval of the aggregate call's Aggref node, which may have other uses beyond the immediate need. There is also support for ordered-set aggregates to install cleanup callback functions, so that they can be sure that infrastructure such as tuplesort objects gets cleaned up. In passing, make some fixes in the recently-added support for variadic aggregates, and make some editorial adjustments in the recent FILTER additions for aggregates. Also, simplify use of IsBinaryCoercible() by allowing it to succeed whenever the target type is ANY or ANYELEMENT. It was inconsistent that it dealt with other polymorphic target types but not these. Atri Sharma and Andrew Gierth; reviewed by Pavel Stehule and Vik Fearing, and rather heavily editorialized upon by Tom Lane
* Implement the FILTER clause for aggregate function calls.Noah Misch2013-07-16
| | | | | | | | | This is SQL-standard with a few extensions, namely support for subqueries and outer references in clause expressions. catversion bump due to change in Aggref and WindowFunc. David Fetter, reviewed by Dean Rasheed.
* pgindent run for release 9.3Bruce Momjian2013-05-29
| | | | | This is the first run of the Perl-based pgindent script. Also update pgindent instructions.
* Editorialize a bit on new ProcessUtility() API.Tom Lane2013-04-28
| | | | | | | | Choose a saner ordering of parameters (adding a new input param after the output params seemed a bit random), update the function's header comment to match reality (cmon folks, is this really that hard?), get rid of useless and sloppily-defined distinction between PROCESS_UTILITY_SUBCOMMAND and PROCESS_UTILITY_GENERATED.
* 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.
* Update copyrights for 2013Bruce Momjian2013-01-01
| | | | | Fully update git head, and update back branches in ./COPYRIGHT and legal.sgml files.
* Get rid of COERCE_DONTCARE.Tom Lane2012-10-12
| | | | We don't need this hack any more.
* 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.
* 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