23 Commits (01ba7894f3f72ea57d1cfdc4f40f6231bc6cd9cd)

Author	SHA1	Message	Date
Tom Lane	f4abd0241d	Support flattening of empty-FROM subqueries and one-row VALUES tables. ... We can't handle this in the general case due to limitations of the planner's data representations; but we can allow it in many useful cases, by being careful to flatten only when we are pulling a single-row subquery up into a FROM (or, equivalently, inner JOIN) node that will still have at least one remaining relation child. Per discussion of an example from Kyotaro Horiguchi.	11 years ago
Tom Lane	f330a6d140	Fix mishandling of FieldSelect-on-whole-row-Var in nested lateral queries. ... If an inline-able SQL function taking a composite argument is used in a LATERAL subselect, and the composite argument is a lateral reference, the planner could fail with "variable not found in subplan target list", as seen in bug #11703 from Karl Bartel. (The outer function call used in the bug report and in the committed regression test is not really necessary to provoke the bug --- you can get it if you manually expand the outer function into "LATERAL (SELECT inner_function(outer_relation))", too.) The cause of this is that we generate the reltargetlist for the referenced relation before doing eval_const_expressions() on the lateral sub-select's expressions (cf find_lateral_references()), so what's scheduled to be emitted by the referenced relation is a whole-row Var, not the simplified single-column Var produced by optimizing the function's FieldSelect on the whole-row Var. Then setrefs.c fails to match up that lateral reference to what's available from the outer scan. Preserving the FieldSelect optimization in such cases would require either major planner restructuring (to recursively do expression simplification on sub-selects much earlier) or some amazingly ugly kluge to change the reltargetlist of a possibly-already-planned relation. It seems better just to skip the optimization when the Var is from an upper query level; the case is not so common that it's likely anyone will notice a few wasted cycles. AFAICT this problem only occurs for uplevel LATERAL references, so back-patch to 9.3 where LATERAL was added.	11 years ago
Tom Lane	080b7db72e	Fix "cannot accept a set" error when only some arms of a CASE return a set. ... In commit c1352052ef, I implemented an optimization that assumed that a function's argument expressions would either always return a set (ie multiple rows), or always not. This is wrong however: we allow CASE expressions in which some arms return a set of some type and others just return a scalar of that type. There may be other examples as well. To fix, replace the run-time test of whether an argument returned a set with a static precheck (expression_returns_set). This adds a little bit of query startup overhead, but it seems barely measurable. Per bug #8228 from David Johnston. This has been broken since 8.0, so patch all supported branches.	12 years ago
Noah Misch	53685d7981	Rename TABLE() to ROWS FROM(). ... SQL-standard TABLE() is a subset of UNNEST(); they deal with arrays and other collection types. This feature, however, deals with set-returning functions. Use a different syntax for this feature to keep open the possibility of implementing the standard TABLE().	12 years ago
Tom Lane	784e762e88	Support multi-argument UNNEST(), and TABLE() syntax for multiple functions. ... This patch adds the ability to write TABLE( function1(), function2(), ...) as a single FROM-clause entry. The result is the concatenation of the first row from each function, followed by the second row from each function, etc; with NULLs inserted if any function produces fewer rows than others. This is believed to be a much more useful behavior than what Postgres currently does with multiple SRFs in a SELECT list. This syntax also provides a reasonable way to combine use of column definition lists with WITH ORDINALITY: put the column definition list inside TABLE(), where it's clear that it doesn't control the ordinality column as well. Also implement SQL-compliant multiple-argument UNNEST(), by turning UNNEST(a,b,c) into TABLE(unnest(a), unnest(b), unnest(c)). The SQL standard specifies TABLE() with only a single function, not multiple functions, and it seems to require an implicit UNNEST() which is not what this patch does. There may be something wrong with that reading of the spec, though, because if it's right then the spec's TABLE() is just a pointless alternative spelling of UNNEST(). After further review of that, we might choose to adopt a different syntax for what this patch does, but in any case this functionality seems clearly worthwhile. Andrew Gierth, reviewed by Zoltán Böszörményi and Heikki Linnakangas, and significantly revised by me	12 years ago
Tom Lane	fcf9ecad57	In locate_grouping_columns(), don't expect an exact match of Var typmods. ... It's possible that inlining of SQL functions (or perhaps other changes?) has exposed typmod information not known at parse time. In such cases, Vars generated by query_planner might have valid typmod values while the original grouping columns only have typmod -1. This isn't a semantic problem since the behavior of grouping only depends on type not typmod, but it breaks locate_grouping_columns' use of tlist_member to locate the matching entry in query_planner's result tlist. We can fix this without an excessive amount of new code or complexity by relying on the fact that locate_grouping_columns only gets called when make_subplanTargetList has set need_tlist_eval == false, and that can only happen if all the grouping columns are simple Vars. Therefore we only need to search the sub_tlist for a matching Var, and we can reasonably define a "match" as being a match of the Var identity fields varno/varattno/varlevelsup. The code still Asserts that vartype matches, but ignores vartypmod. Per bug #8393 from Evan Martin. The added regression test case is basically the same as his example. This has been broken for a very long time, so back-patch to all supported branches.	13 years ago
Greg Stark	c62736cc37	Add SQL Standard WITH ORDINALITY support for UNNEST (and any other SRF) ... Author: Andrew Gierth, David Fetter Reviewers: Dean Rasheed, Jeevan Chalke, Stephen Frost	13 years ago
Tom Lane	2378d79ab2	Make LATERAL implicit for functions in FROM. ... The SQL standard does not have general functions-in-FROM, but it does allow UNNEST() there (see the <collection derived table> production), and the semantics of that are defined to include lateral references. So spec compliance requires allowing lateral references within UNNEST() even without an explicit LATERAL keyword. Rather than making UNNEST() a special case, it seems best to extend this flexibility to any function-in-FROM. We'll still allow LATERAL to be written explicitly for clarity's sake, but it's now a noise word in this context. In theory this change could result in a change in behavior of existing queries, by allowing what had been an outer reference in a function-in-FROM to be captured by an earlier FROM-item at the same level. However, all pre-9.3 PG releases have a bug that causes them to match variable references to earlier FROM-items in preference to outer references (and then throw an error). So no previously-working query could contain the type of ambiguity that would risk a change of behavior. Per a suggestion from Andrew Gierth, though I didn't use his patch.	13 years ago
Tom Lane	225f0aa3df	Prevent inlining a SQL function with multiple OUT parameters. ... There were corner cases in which the planner would attempt to inline such a function, which would result in a failure at runtime due to loss of information about exactly what the result record type is. Fix by disabling inlining when the function's recorded result type is RECORD. There might be some sub-cases where inlining could still be allowed, but this is a simple and backpatchable fix, so leave refinements for another day. Per bug #5777 from Nate Carson. Back-patch to all supported branches. 8.1 happens to avoid a core-dump here, but it still does the wrong thing.	15 years ago
Tom Lane	53e757689c	Make NestLoop plan nodes pass outer-relation variables into their inner ... relation using the general PARAM_EXEC executor parameter mechanism, rather than the ad-hoc kluge of passing the outer tuple down through ExecReScan. The previous method was hard to understand and could never be extended to handle parameters coming from multiple join levels. This patch doesn't change the set of possible plans nor have any significant performance effect, but it's necessary infrastructure for future generalization of the concept of an inner indexscan plan. ExecReScan's second parameter is now unused, so it's removed.	16 years ago
Tom Lane	a620d5005d	Fix a bug introduced when set-returning SQL functions were made inline-able: ... we have to cope with the possibility that the declared result rowtype contains dropped columns. This fails in 8.4, as per bug #5240. While at it, be more paranoid about inserting binary coercions when inlining. The pre-8.4 code did not really need to worry about that because it could not inline at all in any case where an added coercion could change the behavior of the function's statement. However, when inlining a SRF we allow sorting, grouping, and set-ops such as UNION. In these cases, modifying one of the targetlist entries that the sort/group/setop depends on could conceivably change the behavior of the function's statement --- so don't inline when such a case applies.	16 years ago
Tom Lane	717fa274d1	Support use of function argument names to identify which actual arguments ... match which function parameters. The syntax uses AS, for example funcname(value AS arg1, anothervalue AS arg2) Pavel Stehule	17 years ago
Tom Lane	0c19f05803	Fix things so that you can still do "select foo()" where foo is a SQL ... function returning setof record. This used to work, more or less accidentally, but I had broken it while extending the code to allow materialize-mode functions to be called in select lists. Add a regression test case so it doesn't get broken again. Per gripe from Greg Davidson.	17 years ago
Tom Lane	793d5662e8	Fix an oversight in the support for storing/retrieving "minimal tuples" in ... TupleTableSlots. We have functions for retrieving a minimal tuple from a slot after storing a regular tuple in it, or vice versa; but these were implemented by converting the internal storage from one format to the other. The problem with that is it invalidates any pass-by-reference Datums that were already fetched from the slot, since they'll be pointing into the just-freed version of the tuple. The known problem cases involve fetching both a whole-row variable and a pass-by-reference value from a slot that is fed from a tuplestore or tuplesort object. The added regression tests illustrate some simple cases, but there may be other failure scenarios traceable to the same bug. Note that the added tests probably only fail on unpatched code if it's built with --enable-cassert; otherwise the bug leads to fetching from freed memory, which will not have been overwritten without additional conditions. Fix by allowing a slot to contain both formats simultaneously; which turns out not to complicate the logic much at all, if anything it seems less contorted than before. Back-patch to 8.2, where minimal tuples were introduced.	17 years ago
Tom Lane	9b46abb7c4	Allow SQL-language functions to return the output of an INSERT/UPDATE/DELETE ... RETURNING clause, not just a SELECT as formerly. A side effect of this patch is that when a set-returning SQL function is used in a FROM clause, performance is improved because the output is collected into a tuplestore within the function, rather than using the less efficient value-per-call mechanism.	17 years ago
Tom Lane	69a785b8bf	Implement SQL-spec RETURNS TABLE syntax for functions. ... (Unlike the original submission, this patch treats TABLE output parameters as being entirely equivalent to OUT parameters -- tgl) Pavel Stehule	18 years ago
Peter Eisentraut	7f4f42fa10	Clean up CREATE FUNCTION syntax usage in contrib and elsewhere, in ... particular get rid of single quotes around language names and old WITH () construct.	20 years ago
Tom Lane	47888fe842	First phase of OUT-parameters project. We can now define and use SQL ... functions with OUT parameters. The various PLs still need work, as does pg_dump. Rudimentary docs and regression tests included.	21 years ago
Bruce Momjian	38fb906f93	> Joe Conway <mail@joeconway.com> writes: ... >>ISTM that "source" is worth knowing. > > Hm, possibly. Any other opinions? This version has the seven fields I proposed, including "source". Here's an example that shows why I think it's valuable: regression=# \x Expanded display is on. regression=# select * from pg_settings where name = 'enable_seqscan'; -[ RECORD 1 ]----------- name | enable_seqscan setting | on context | user vartype | bool source | default min_val | max_val | regression=# update pg_settings set setting = 'off' where name = 'enable_seqscan'; -[ RECORD 1 ]--- set_config | off regression=# select * from pg_settings where name = 'enable_seqscan'; -[ RECORD 1 ]----------- name | enable_seqscan setting | off context | user vartype | bool source | session min_val | max_val | regression=# alter user postgres set enable_seqscan to 'off'; ALTER USER (log out and then back in again) regression=# \x Expanded display is on. regression=# select * from pg_settings where name = 'enable_seqscan'; -[ RECORD 1 ]----------- name | enable_seqscan setting | off context | user vartype | bool source | user min_val | max_val | In the first case, enable_seqscan is set to its default value. After setting it to off, it is obvious that the value has been changed for the session only. In the third case, you can see that the value has been set specifically for the user. Joe Conway	23 years ago
Tom Lane	549928d99b	Fix for breakage of C-coded SRFs, from Joe Conway.	24 years ago
Tom Lane	64505ed58b	Code review for standalone composite types, query-specified composite ... types, SRFs. Not happy with memory management yet, but I'll commit these other changes.	24 years ago
Tom Lane	30ec31604d	Add code to extract dependencies from an expression tree, and use it ... to build dependencies for rules, constraint expressions, and default expressions. Repair some problems in the original design of recursiveDeletion() exposed by more complex dependency sets. Fix regression tests that were deleting things in illegal sequences.	24 years ago
Bruce Momjian	95712b15b1	Add missing regression files for SRF.	24 years ago