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* Revert temporal primary keys and foreign keysPeter Eisentraut2024-05-16
| | | | | | | | | | | | | | | | | | | | This feature set did not handle empty ranges correctly, and it's now too late for PostgreSQL 17 to fix it. The following commits are reverted: 6db4598fcb8 Add stratnum GiST support function 46a0cd4cefb Add temporal PRIMARY KEY and UNIQUE constraints 86232a49a43 Fix comment on gist_stratnum_btree 030e10ff1a3 Rename pg_constraint.conwithoutoverlaps to conperiod a88c800deb6 Use daterange and YMD in without_overlaps tests instead of tsrange. 5577a71fb0c Use half-open interval notation in without_overlaps tests 34768ee3616 Add temporal FOREIGN KEY contraints 482e108cd38 Add test for REPLICA IDENTITY with a temporal key c3db1f30cba doc: clarify PERIOD and WITHOUT OVERLAPS in CREATE TABLE 144c2ce0cc7 Fix ON CONFLICT DO NOTHING/UPDATE for temporal indexes Discussion: https://www.postgresql.org/message-id/d0b64a7a-dfe4-4b84-a906-c7dedfa40a3e@eisentraut.org
* Revert structural changes to not-null constraintsAlvaro Herrera2024-05-13
| | | | | | | | | | | | | | | | | | | | | | | | | There are some problems with the new way to handle these constraints that were detected at the last minute, and require fixes that appear too invasive to be doing this late in the cycle. Revert this (again) for now, we'll try again with these problems fixed. The following commits are reverted: b0e96f311985 Catalog not-null constraints 9b581c534186 Disallow changing NO INHERIT status of a not-null constraint d0ec2ddbe088 Fix not-null constraint test ac22a9545ca9 Move privilege check to the right place b0f7dd915bca Check stack depth in new recursive functions 3af721794272 Update information_schema definition for not-null constraints c3709100be73 Fix propagating attnotnull in multiple inheritance d9f686a72ee9 Fix restore of not-null constraints with inheritance d72d32f52d26 Don't try to assign smart names to constraints 0cd711271d42 Better handle indirect constraint drops 13daa33fa5a6 Disallow NO INHERIT not-null constraints on partitioned tables d45597f72fe5 Disallow direct change of NO INHERIT of not-null constraints 21ac38f498b3 Fix inconsistencies in error messages Discussion: https://postgr.es/m/202405110940.joxlqcx4dogd@alvherre.pgsql
* Fix ON CONFLICT DO NOTHING/UPDATE for temporal indexesPeter Eisentraut2024-05-10
| | | | | | | | | | | | | | A PRIMARY KEY or UNIQUE constraint with WITHOUT OVERLAPS will be a GiST index, not a B-Tree, but it will still have indisunique set. The code for ON CONFLICT fails if it sees a non-btree index that has indisunique. This commit fixes that and adds some tests. But now that we can't just test indisunique, we also need some extra checks to prevent DO UPDATE from running against a WITHOUT OVERLAPS constraint (because the conflict could happen against more than one row, and we'd only update one). Author: Paul A. Jungwirth <pj@illuminatedcomputing.com> Discussion: https://www.postgresql.org/message-id/1426589a-83cb-4a89-bf40-713970c07e63@illuminatedcomputing.com
* Fix query pullup issue with WindowClause runConditionDavid Rowley2024-05-05
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 94985c210 added code to detect when WindowFuncs were monotonic and allowed additional quals to be "pushed down" into the subquery to be used as WindowClause runConditions in order to short-circuit execution in nodeWindowAgg.c. The Node representation of runConditions wasn't well selected and because we do qual pushdown before planning the subquery, the planning of the subquery could perform subquery pull-up of nested subqueries. For WindowFuncs with args, the arguments could be changed after pushing the qual down to the subquery. This was made more difficult by the fact that the code duplicated the WindowFunc inside an OpExpr to include in the WindowClauses runCondition field. This could result in duplication of subqueries and a pull-up of such a subquery could result in another initplan parameter being issued for the 2nd version of the subplan. This could result in errors such as: ERROR: WindowFunc not found in subplan target lists To fix this, we change the node representation of these run conditions and instead of storing an OpExpr containing the WindowFunc in a list inside WindowClause, we now store a new node type named WindowFuncRunCondition within a new field in the WindowFunc. These get transformed into OpExprs later in planning once subquery pull-up has been performed. This problem did exist in v15 and v16, but that was fixed by 9d36b883b and e5d20bbd. Cat version bump due to new node type and modifying WindowFunc struct. Bug: #18305 Reported-by: Zuming Jiang Discussion: https://postgr.es/m/18305-33c49b4c830b37b3%40postgresql.org
* Ensure generated join clauses for child rels have correct relids.Tom Lane2024-04-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When building a join clause derived from an EquivalenceClass, if the clause is to be used with an appendrel child relation then make sure its clause_relids include the relids of that child relation. Normally this would be true already because the EquivalenceMember would be a Var of that relation. However, if the appendrel represents a flattened UNION ALL construct then some child EquivalenceMembers could be constants with no relids. The resulting under-marked clause is problematic because it could mislead join_clause_is_movable_into about where the clause should be evaluated. We do not have an example showing incorrect plan generation, but there are existing cases in the regression tests that will fail the Asserts this patch adds to get_baserel_parampathinfo. A similarly wrong conclusion about a clause being considered by get_joinrel_parampathinfo would lead to wrong placement of the clause. (This also squares with the way that clause_relids is calculated for non-equijoin clauses in adjust_appendrel_attrs.) The other reason for wanting these new Asserts is that the previous blithe assumption that the results of generate_join_implied_equalities "necessarily satisfy join_clause_is_movable_into" turns out to be wrong pre-v16. If it's still wrong it'd be good to find out. Per bug #18429 from Benoît Ryder. The bug as filed was fixed by commit 2489d76c4, but these changes correlate with the fix we will need to apply in pre-v16 branches. Discussion: https://postgr.es/m/18429-8982d4a348cc86c6@postgresql.org
* Fix type-checking of RECORD-returning functions in FROM, redux.Tom Lane2024-04-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 2ed8f9a01 intended to institute a policy that if a RangeTblFunction has a coldeflist, then the function return type is certainly RECORD, and we should use the coldeflist as the source of truth about what the columns of the record type are. When the original function has been folded to a constant, inspection of the constant might give a different answer. This situation will lead to a tuple-type-mismatch error at execution, but up until that point we need to consistently believe the coldeflist, or we'll have problems from different bits of code reaching different conclusions. expandRTE didn't get that memo though, and would try to produce a tupdesc based on the constant in this situation, leading to an assertion failure. (Desultory testing suggests that non-assert builds often manage to give the expected error, although I also saw a "cache lookup failed for type 0" error, and it seems at least possible that a crash could happen.) Some other callers of get_expr_result_type and get_expr_result_tupdesc were also being incautious about this. While none of them seem to have actual bugs, they're working harder than necessary in this case, besides which it seems safest to have an explicit policy of not using those functions on an RTE with a coldeflist. Adjust the code accordingly, and add commentary to funcapi.c about this policy. Also fix an obsolete comment that claimed "get_expr_result_type() doesn't know how to extract type info from a RECORD constant". That hasn't been true since commit d57534740. Per bug #18422 from Alexander Lakhin. As with the previous commit, back-patch to all supported branches. Discussion: https://postgr.es/m/18422-89ca86c8eac5246d@postgresql.org
* Fix IS [NOT] NULL qual optimization for inheritance tablesDavid Rowley2024-04-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | b262ad440 added code to have the planner remove redundant IS NOT NULL quals and eliminate needless scans for IS NULL quals on tables where the qual's column has a NOT NULL constraint. That commit failed to consider that an inheritance parent table could have differing NOT NULL constraints between the parent and the child. This caused issues as if we eliminated a qual on the parent, when applying the quals to child tables in apply_child_basequals(), the qual might not have been added to the parent's baserestrictinfo. Here we fix this by not applying the optimization to remove redundant quals to RelOptInfos belonging to inheritance parents and applying the optimization again in apply_child_basequals(). Effectively, this means that the parent and child are considered independently as the parent has both an inh=true and inh=false RTE and we still apply the optimization to the RelOptInfo corresponding to the inh=false RTE. We're able to still apply the optimization in add_base_clause_to_rel() for partitioned tables as the NULLability of partitions must match that of their parent. And, if we ever expand restriction_is_always_false() and restriction_is_always_true() to handle partition constraints then we can apply the same logic as, even in multi-level partitioned tables, there's no way to route values to a partition when the qual does not match the partition qual of the partitioned table's parent partition. The same is true for CHECK constraints as those must also match between arent partitioned tables and their partitions. Author: Richard Guo, David Rowley Discussion: https://postgr.es/m/CAMbWs4930gQSZmjR7aANzEapdy61gCg6z8dT-kAEYD0sYWKPdQ@mail.gmail.com
* Add support for MERGE ... WHEN NOT MATCHED BY SOURCE.Dean Rasheed2024-03-30
| | | | | | | | | | | | | | | | | | | This allows MERGE commands to include WHEN NOT MATCHED BY SOURCE actions, which operate on rows that exist in the target relation, but not in the data source. These actions can execute UPDATE, DELETE, or DO NOTHING sub-commands. This is in contrast to already-supported WHEN NOT MATCHED actions, which operate on rows that exist in the data source, but not in the target relation. To make this distinction clearer, such actions may now be written as WHEN NOT MATCHED BY TARGET. Writing WHEN NOT MATCHED without specifying BY SOURCE or BY TARGET is equivalent to writing WHEN NOT MATCHED BY TARGET. Dean Rasheed, reviewed by Alvaro Herrera, Ted Yu and Vik Fearing. Discussion: https://postgr.es/m/CAEZATCWqnKGc57Y_JanUBHQXNKcXd7r=0R4NEZUVwP+syRkWbA@mail.gmail.com
* Propagate pathkeys from CTEs up to the outer query.Tom Lane2024-03-26
| | | | | | | | | | | | | | | | | | | | | | | If we know the sort order of a CTE's output, and it is relevant to the outer query, label the CTE's outer-query access path using those pathkeys. This may enable optimizations such as avoiding a sort in the outer query. The code for hoisting pathkeys into the outer query already exists for regular RTE_SUBQUERY subqueries, but it wasn't getting used for CTEs, possibly out of concern for maintaining an optimization fence between the CTE and the outer query. However, on the same arguments used for commit f7816aec2, there seems no harm in letting the outer query know what the inner query decided to do. In support of this, we now remember the best Path as well as Plan for each subquery for the rest of the planner run. There may be future applications for having that at hand, and it surely costs little to build one more List. Richard Guo (minor mods by me) Discussion: https://postgr.es/m/CAMbWs49xYd3f8CrE8-WW3--dV1zH_sDSDn-vs2DzHj81Wcnsew@mail.gmail.com
* Refactor predicate_{implied,refuted}_by_simple_clause.Tom Lane2024-03-25
| | | | | | | | | | | | | Put the node-type-dependent operations into switches on nodeTag. This should ease addition of new proof rules for other expression node types. There is no functional change, although some tests are made in a different order than before. Also, add a couple of new cross-checks in test_predtest.c. James Coleman (part of a larger patch series) Discussion: https://postgr.es/m/CAAaqYe8Bo4bf_i6qKj8KBsmHMYXhe3Xt6vOe3OBQnOaf3_XBWg@mail.gmail.com
* Code review for 6190d828cd2Amit Langote2024-03-25
| | | | | | | | | | | | | * Fix the comment of init_dummy_sjinfo() to remove references to non-existing parameters 'rel1' and 'rel2'. * Adjust consider_new_or_clause() to call init_dummy_sjinfo() to make up a SpecialJoinInfo for inner joins like other code sites that were adjusted in 6190d828cd2 to do so. Author: Richard Guo <guofenglinux@gmail.com> Reported-by: Richard Guo <guofenglinux@gmail.com> Discussion: https://postgr.es/m/CAExHW5tHqEf3ASVqvFFcghYGPfpy7o3xnvhHwBGbJFMRH8KjNw@mail.gmail.com
* Reduce memory used by partitionwise joinsAmit Langote2024-03-25
| | | | | | | | | | | | | | | | | | | | | Specifically, this commit reduces the memory consumed by the SpecialJoinInfos that are allocated for child joins in try_partitionwise_join() by freeing them at the end of creating paths for each child join. A SpecialJoinInfo allocated for a given child join is a copy of the parent join's SpecialJoinInfo, which contains the translated copies of the various Relids bitmapsets and semi_rhs_exprs, which is a List of Nodes. The newly added freeing step frees the struct itself and the various bitmapsets, but not semi_rhs_exprs, because there's no handy function to free the memory of Node trees. Author: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com> Reviewed-by: Richard Guo <guofenglinux@gmail.com> Reviewed-by: Amit Langote <amitlangote09@gmail.com> Reviewed-by: Andrey Lepikhov <a.lepikhov@postgrespro.ru> Reviewed-by: Tomas Vondra <tomas.vondra@enterprisedb.com> Discussion: https://postgr.es/m/CAExHW5tHqEf3ASVqvFFcghYGPfpy7o3xnvhHwBGbJFMRH8KjNw@mail.gmail.com
* Add SQL/JSON query functionsAmit Langote2024-03-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This introduces the following SQL/JSON functions for querying JSON data using jsonpath expressions: JSON_EXISTS(), which can be used to apply a jsonpath expression to a JSON value to check if it yields any values. JSON_QUERY(), which can be used to to apply a jsonpath expression to a JSON value to get a JSON object, an array, or a string. There are various options to control whether multi-value result uses array wrappers and whether the singleton scalar strings are quoted or not. JSON_VALUE(), which can be used to apply a jsonpath expression to a JSON value to return a single scalar value, producing an error if it multiple values are matched. Both JSON_VALUE() and JSON_QUERY() functions have options for handling EMPTY and ERROR conditions, which can be used to specify the behavior when no values are matched and when an error occurs during jsonpath evaluation, respectively. Author: Nikita Glukhov <n.gluhov@postgrespro.ru> Author: Teodor Sigaev <teodor@sigaev.ru> Author: Oleg Bartunov <obartunov@gmail.com> Author: Alexander Korotkov <aekorotkov@gmail.com> Author: Andrew Dunstan <andrew@dunslane.net> Author: Amit Langote <amitlangote09@gmail.com> Author: Peter Eisentraut <peter@eisentraut.org> Author: Jian He <jian.universality@gmail.com> Reviewers have included (in no particular order): Andres Freund, Alexander Korotkov, Pavel Stehule, Andrew Alsup, Erik Rijkers, Zihong Yu, Himanshu Upadhyaya, Daniel Gustafsson, Justin Pryzby, Álvaro Herrera, Jian He, Anton A. Melnikov, Nikita Malakhov, Peter Eisentraut, Tomas Vondra Discussion: https://postgr.es/m/cd0bb935-0158-78a7-08b5-904886deac4b@postgrespro.ru Discussion: https://postgr.es/m/20220616233130.rparivafipt6doj3@alap3.anarazel.de Discussion: https://postgr.es/m/abd9b83b-aa66-f230-3d6d-734817f0995d%40postgresql.org Discussion: https://postgr.es/m/CA+HiwqHROpf9e644D8BRqYvaAPmgBZVup-xKMDPk-nd4EpgzHw@mail.gmail.com Discussion: https://postgr.es/m/CA+HiwqE4XTdfb1nW=Ojoy_tQSRhYt-q_kb6i5d4xcKyrLC1Nbg@mail.gmail.com
* Postpone reparameterization of paths until create_plan().Tom Lane2024-03-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When considering nestloop paths for individual partitions within a partitionwise join, if the inner path is parameterized, it is parameterized by the topmost parent of the outer rel, not the corresponding outer rel itself. Therefore, we need to translate the parameterization so that the inner path is parameterized by the corresponding outer rel. Up to now, we did this while generating join paths. However, that's problematic because we must also translate some expressions that are shared across all paths for a relation, such as restriction clauses (kept in the RelOptInfo and/or IndexOptInfo) and TableSampleClauses (kept in the RangeTblEntry). The existing code fails to translate these at all, leading to wrong answers, odd failures such as "variable not found in subplan target list", or executor crashes. But we can't modify them during path generation, because that would break things if we end up choosing some non-partitioned-join path. So this patch postpones reparameterization of the inner path until createplan.c, where it is safe to modify the referenced RangeTblEntry, RelOptInfo or IndexOptInfo, because we have made a final choice of which Path to use. We do still have to check during path generation that the reparameterization will be possible. So we introduce a new function path_is_reparameterizable_by_child() to detect that. The duplication between path_is_reparameterizable_by_child() and reparameterize_path_by_child() is a bit annoying, but there seems no other good answer. A small benefit is that we can avoid building useless reparameterized trees in cases where a non-partitioned join is ultimately chosen. Also, reparameterize_path_by_child() can now be allowed to scribble on the input paths, saving a few cycles. This fix repairs the same problems previously addressed in the back branches by commits 62f120203 et al. Richard Guo, reviewed at various times by Ashutosh Bapat, Andrei Lepikhov, Alena Rybakina, Robert Haas, and myself Discussion: https://postgr.es/m/CAMbWs496+N=UAjOc=rcD3P7B6oJe4rZw08e_TZRUsWbPxZW3Tw@mail.gmail.com
* Add RETURNING support to MERGE.Dean Rasheed2024-03-17
| | | | | | | | | | | | | | | | | | | | | | | | | | This allows a RETURNING clause to be appended to a MERGE query, to return values based on each row inserted, updated, or deleted. As with plain INSERT, UPDATE, and DELETE commands, the returned values are based on the new contents of the target table for INSERT and UPDATE actions, and on its old contents for DELETE actions. Values from the source relation may also be returned. As with INSERT/UPDATE/DELETE, the output of MERGE ... RETURNING may be used as the source relation for other operations such as WITH queries and COPY commands. Additionally, a special function merge_action() is provided, which returns 'INSERT', 'UPDATE', or 'DELETE', depending on the action executed for each row. The merge_action() function can be used anywhere in the RETURNING list, including in arbitrary expressions and subqueries, but it is an error to use it anywhere outside of a MERGE query's RETURNING list. Dean Rasheed, reviewed by Isaac Morland, Vik Fearing, Alvaro Herrera, Gurjeet Singh, Jian He, Jeff Davis, Merlin Moncure, Peter Eisentraut, and Wolfgang Walther. Discussion: http://postgr.es/m/CAEZATCWePEGQR5LBn-vD6SfeLZafzEm2Qy_L_Oky2=qw2w3Pzg@mail.gmail.com
* Make the order of the header file includes consistentPeter Eisentraut2024-03-13
| | | | | | | | Similar to commit 7e735035f20. Author: Richard Guo <guofenglinux@gmail.com> Reviewed-by: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com> Discussion: https://www.postgresql.org/message-id/flat/CAMbWs4-WhpCFMbXCjtJ%2BFzmjfPrp7Hw1pk4p%2BZpU95Kh3ofZ1A%40mail.gmail.com
* Fix confusion about the return rowtype of SQL-language procedures.Tom Lane2024-03-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | There is a very ancient hack in check_sql_fn_retval that allows a single SELECT targetlist entry of composite type to be taken as supplying all the output columns of a function returning composite. (This is grotty and fundamentally ambiguous, but it's really hard to do nested composite-returning functions without it.) As far as I know, that doesn't cause any problems in ordinary functions. It's disastrous for procedures however. All procedures that have any output parameters are labeled with prorettype RECORD, and the CALL code expects it will get back a record with one column per output parameter, regardless of whether any of those parameters is composite. Doing something else leads to an assertion failure or core dump. This is simple enough to fix: we just need to not apply that rule when considering procedures. However, that requires adding another argument to check_sql_fn_retval, which at least in principle might be getting called by external callers. Therefore, in the back branches convert check_sql_fn_retval into an ABI-preserving wrapper around a new function check_sql_fn_retval_ext. Per report from Yahor Yuzefovich. This has been broken since we implemented procedures, so back-patch to all supported branches. Discussion: https://postgr.es/m/CABz5gWHSjj2df6uG0NRiDhZ_Uz=Y8t0FJP-_SVSsRsnrQT76Gg@mail.gmail.com
* Fix type-checking of RECORD-returning functions in FROM.Tom Lane2024-03-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the corner case where a function returning RECORD has been simplified to a RECORD constant or an inlined ROW() expression, ExecInitFunctionScan failed to cross-check the function's result rowtype against the coldeflist provided by the calling query. That happened because get_expr_result_type is able to extract a tupdesc from such expressions, which led ExecInitFunctionScan to ignore the coldeflist. (Instead, it used the extracted tupdesc to check the function's output, which of course always succeeds.) I have not been able to demonstrate any really serious consequences from this, because if some column of the result is of the wrong type and is directly referenced by a Var of the calling query, CheckVarSlotCompatibility will catch it. However, we definitely do fail to report the case where the function returns more columns than the coldeflist expects, and in the converse case where it returns fewer columns, we get an assert failure (but, seemingly, no worse results in non-assert builds). To fix, always build the expected tupdesc from the coldeflist if there is one, and consult get_expr_result_type only when there isn't one. Also remove the failing Assert, even though it is no longer reached after this fix. It doesn't seem to be adding anything useful, since later checking will deal with cases with the wrong number of columns. The only other place I could find that is doing something similar is inline_set_returning_function. There's no live bug there because we cannot be looking at a Const or RowExpr, but for consistency change that code to agree with ExecInitFunctionScan. Per report from PetSerAl. After some debate I've concluded that this should be back-patched. There is a small risk that somebody has been relying on such a case not throwing an error, but I judge this outweighed by the risk that I've missed some way in which the failure to cross-check has worse consequences than sketched above. Discussion: https://postgr.es/m/CAKygsHSerA1eXsJHR9wft3Gn3wfHQ5RfP8XHBzF70_qcrrRvEg@mail.gmail.com
* Remove unused #include's from backend .c filesPeter Eisentraut2024-03-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | as determined by include-what-you-use (IWYU) While IWYU also suggests to *add* a bunch of #include's (which is its main purpose), this patch does not do that. In some cases, a more specific #include replaces another less specific one. Some manual adjustments of the automatic result: - IWYU currently doesn't know about includes that provide global variable declarations (like -Wmissing-variable-declarations), so those includes are being kept manually. - All includes for port(ability) headers are being kept for now, to play it safe. - No changes of catalog/pg_foo.h to catalog/pg_foo_d.h, to keep the patch from exploding in size. Note that this patch touches just *.c files, so nothing declared in header files changes in hidden ways. As a small example, in src/backend/access/transam/rmgr.c, some IWYU pragma annotations are added to handle a special case there. Discussion: https://www.postgresql.org/message-id/flat/af837490-6b2f-46df-ba05-37ea6a6653fc%40eisentraut.org
* Support MERGE into updatable views.Dean Rasheed2024-02-29
| | | | | | | | | | | | | | | | | | | This allows the target relation of MERGE to be an auto-updatable or trigger-updatable view, and includes support for WITH CHECK OPTION, security barrier views, and security invoker views. A trigger-updatable view must have INSTEAD OF triggers for every type of action (INSERT, UPDATE, and DELETE) mentioned in the MERGE command. An auto-updatable view must not have any INSTEAD OF triggers. Mixing auto-update and trigger-update actions (i.e., having a partial set of INSTEAD OF triggers) is not supported. Rule-updatable views are also not supported, since there is no rewriter support for non-SELECT rules with MERGE operations. Dean Rasheed, reviewed by Jian He and Alvaro Herrera. Discussion: https://postgr.es/m/CAEZATCVcB1g0nmxuEc-A+gGB0HnfcGQNGYH7gS=7rq0u0zOBXA@mail.gmail.com
* Avoid dangling-pointer problem with partitionwise joins under GEQO.Tom Lane2024-02-23
| | | | | | | | | | | | | | | | build_child_join_sjinfo creates a derived SpecialJoinInfo in the short-lived GEQO context, but afterwards the semi_rhs_exprs from that may be used in a UniquePath for a child base relation. This breaks the expectation that all base-relation-level structures are in the planning-lifespan context, leading to use of a dangling pointer with probable ensuing crash later on in create_unique_plan. To fix, copy the expression trees when making a UniquePath. Per bug #18360 from Alexander Lakhin. This has been broken since partitionwise joins were added, so back-patch to all supported branches. Discussion: https://postgr.es/m/18360-a23caf3157f34e62@postgresql.org
* Add missing check_stack_depth() to some recursive functionsAlexander Korotkov2024-02-16
| | | | | Reported-by: Egor Chindyaskin, Alexander Lakhin Discussion: https://postgr.es/m/1672760457.940462079%40f306.i.mail.ru
* Clarify the 'rows' parameter in create_append_pathDavid Rowley2024-02-15
| | | | | | | | | | This is extracted from a larger patch to improve the UNION planner. While working on that, I found myself having to check what the 'rows' parameter is for. It's not obvious that passing a negative number is the way to have the rows estimate calculated and to find that out you need to read code in create_append_path() and in cost_append(). Discussion: https://postgr.es/m/CAApHDvpb_63XQodmxKUF8vb9M7CxyUyT4sWvEgqeQU-GB7QFoQ@mail.gmail.com
* Fix costing bug in MergeAppendDavid Rowley2024-02-01
| | | | | | | | | | | | | | | | | | | | | | | | When building a MergeAppendPath which has child paths that are not sorted correctly for the MergeAppend's sort order, we apply the cost of sorting those paths to the MergeAppendPath costs. Here we fix a bug where the number of tuples specified that needed to be sorted was effectively pg_class.reltuples rather than the number of expected row in the subpath. This effectively penalizes MergeAppend plans any time any filter is present on the MergeAppend subpath as the sort cost added is to sort all tuples in the table rather than just the ones expected the path to return. This did not affect UNION ALL type queries as the RelOptInfo tuples is set from the subquery's path rows. It does affect MergeAppends uses for inheritance and partitioned tables. This is a long-standing bug introduced when MergeAppend was first added in 11cad29c9. No backpatch as this could result in plan changes. Author: Alexander Kuzmenkov Reviewed-by: Ashutosh Bapat, Aleksander Alekseev, David Rowley Discussion: https://postgr.es/m/CALzhyqyhoXQDR-Usd_0HeWk%3DuqNLzoVeT8KhRoo%3DpV_KzgO3QQ%40mail.gmail.com
* Compare varnullingrels too in assign_param_for_var().Tom Lane2024-01-26
| | | | | | | | | Oversight in 2489d76c4. Preliminary analysis suggests that the problem may be unreachable --- but if we did have instances of the same column with different varnullingrels, we'd surely need to treat them as different Params. Discussion: https://postgr.es/m/412552.1706203379@sss.pgh.pa.us
* Add better handling of redundant IS [NOT] NULL qualsDavid Rowley2024-01-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Until now PostgreSQL has not been very smart about optimizing away IS NOT NULL base quals on columns defined as NOT NULL. The evaluation of these needless quals adds overhead. Ordinarily, anyone who came complaining about that would likely just have been told to not include the qual in their query if it's not required. However, a recent bug report indicates this might not always be possible. Bug 17540 highlighted that when we optimize Min/Max aggregates the IS NOT NULL qual that the planner adds to make the rewritten plan ignore NULLs can cause issues with poor index choice. That particular case demonstrated that other quals, especially ones where no statistics are available to allow the planner a chance at estimating an approximate selectivity for can result in poor index choice due to cheap startup paths being prefered with LIMIT 1. Here we take generic approach to fixing this by having the planner check for NOT NULL columns and just have the planner remove these quals (when they're not needed) for all queries, not just when optimizing Min/Max aggregates. Additionally, here we also detect IS NULL quals on a NOT NULL column and transform that into a gating qual so that we don't have to perform the scan at all. This also works for join relations when the Var is not nullable by any outer join. This also helps with the self-join removal work as it must replace strict join quals with IS NOT NULL quals to ensure equivalence with the original query. Author: David Rowley, Richard Guo, Andy Fan Reviewed-by: Richard Guo, David Rowley Discussion: https://postgr.es/m/CAApHDvqg6XZDhYRPz0zgOcevSMo0d3vxA9DvHrZtKfqO30WTnw@mail.gmail.com Discussion: https://postgr.es/m/17540-7aa1855ad5ec18b4%40postgresql.org
* Fix Asserts in calc_non_nestloop_required_outer().Tom Lane2024-01-10
| | | | | | | | | | | | | | These were not testing the same thing as the comparable Assert in calc_nestloop_required_outer(), because we neglected to map the given Paths' relids to top-level relids. When considering a partition child join the latter is the correct thing to do. This oversight is old, but since it's only an overly-weak Assert check there doesn't seem to be much value in back-patching. Richard Guo (with cosmetic changes and comment updates by me) Discussion: https://postgr.es/m/CAMbWs49sqbe9GBZ8sy8dSfKRNURgicR85HX8vgzcgQsPF0XY1w@mail.gmail.com
* Allow examine_simple_variable() to work on INSERT RETURNING Vars.Tom Lane2024-01-08
| | | | | | | | | | | | | | | | | | | | | Since commit 599b33b94, this function assumed that every RTE_RELATION RangeTblEntry would have an associated RelOptInfo. But that's not so: we only build RelOptInfos for relations that are scanned by the query. In particular the target of an INSERT won't have one, so that Vars appearing in an INSERT ... RETURNING list will not have an associated RelOptInfo. This apparently wasn't a problem before commit f7816aec2 taught examine_simple_variable() to drill down into CTEs containing INSERT RETURNING, but it is now. To fix, add a fallback code path that gets the userid to use directly from the RTEPermissionInfo associated with the RTE. (Sadly, we must have two code paths, because not every RTE has a RTEPermissionInfo either.) Per report from Alexander Lakhin. No back-patch, since the case is apparently unreachable before f7816aec2. Discussion: https://postgr.es/m/608a4886-6c60-0f9e-97d5-591256bd4150@gmail.com
* Update copyright for 2024Bruce Momjian2024-01-03
| | | | | | | | Reported-by: Michael Paquier Discussion: https://postgr.es/m/ZZKTDPxBBMt3C0J9@paquier.xyz Backpatch-through: 12
* Prevent integer overflow when forming tuple width estimates.Tom Lane2023-12-19
| | | | | | | | | | | | | | | | | | | | It's at least theoretically possible to overflow int32 when adding up column width estimates to make a row width estimate. (The bug example isn't terribly convincing as a real use-case, but perhaps wide joins would provide a more plausible route to trouble.) This'd lead to assertion failures or silly planner behavior. To forestall it, make the relevant functions compute their running sums in int64 arithmetic and then clamp to int32 range at the end. We can reasonably assume that MaxAllocSize is a hard limit on actual tuple width, so clamping to that is simply a correction for dubious input values, and there's no need to go as far as widening width variables to int64 everywhere. Per bug #18247 from RekGRpth. There've been no reports of this issue arising in practical cases, so I feel no need to back-patch. Richard Guo and Tom Lane Discussion: https://postgr.es/m/18247-11ac477f02954422@postgresql.org
* Ensure we preprocess expressions before checking their volatility.Tom Lane2023-11-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | contain_mutable_functions and contain_volatile_functions give reliable answers only after expression preprocessing (specifically eval_const_expressions). Some places understand this, but some did not get the memo --- which is not entirely their fault, because the problem is documented only in places far away from those functions. Introduce wrapper functions that allow doing the right thing easily, and add commentary in hopes of preventing future mistakes from copy-and-paste of code that's only conditionally safe. Two actual bugs of this ilk are fixed here. We failed to preprocess column GENERATED expressions before checking mutability, so that the code could fail to detect the use of a volatile function default-argument expression, or it could reject a polymorphic function that is actually immutable on the datatype of interest. Likewise, column DEFAULT expressions weren't preprocessed before determining if it's safe to apply the attmissingval mechanism. A false negative would just result in an unnecessary table rewrite, but a false positive could allow the attmissingval mechanism to be used in a case where it should not be, resulting in unexpected initial values in a new column. In passing, re-order the steps in ComputePartitionAttrs so that its checks for invalid column references are done before applying expression_planner, rather than after. The previous coding would not complain if a partition expression contains a disallowed column reference that gets optimized away by constant folding, which seems to me to be a behavior we do not want. Per bug #18097 from Jim Keener. Back-patch to all supported versions. Discussion: https://postgr.es/m/18097-ebb179674f22932f@postgresql.org
* Fix computation of varnullingrels when const-folding field selection.Tom Lane2023-11-09
| | | | | | | | | | | | | We can simplify FieldSelect on a whole-row Var into a plain Var for the selected field. However, we should copy the whole-row Var's varnullingrels when we do so, because the new Var is clearly nullable by exactly the same rels as the original. Failure to do this led to errors like "wrong varnullingrels (b) (expected (b 3)) for Var 2/2". Richard Guo, per bug #18184 from Marian Krucina. Back-patch to v16 where varnullingrels was introduced. Discussion: https://postgr.es/m/18184-5868dd258782058e@postgresql.org
* Avoid compiler warning in non-assert buildsAmit Langote2023-10-26
| | | | | | | | | | | After 01575ad788e3, expand_single_inheritance_child()'s parentOID variable is read only in an Assert, provoking a compiler warning in non-assert builds. Fix that by marking the variable with PG_USED_FOR_ASSERTS_ONLY. Per report and suggestion from David Rowley Discussion: https://postgr.es/m/CAApHDvpjA_8Wxu4DCTRVAvPxC9atwMe6N%2ByvrcGsgb7mrfdpJA%40mail.gmail.com
* Add trailing commas to enum definitionsPeter Eisentraut2023-10-26
| | | | | | | | | | | | | | | | | | | | Since C99, there can be a trailing comma after the last value in an enum definition. A lot of new code has been introducing this style on the fly. Some new patches are now taking an inconsistent approach to this. Some add the last comma on the fly if they add a new last value, some are trying to preserve the existing style in each place, some are even dropping the last comma if there was one. We could nudge this all in a consistent direction if we just add the trailing commas everywhere once. I omitted a few places where there was a fixed "last" value that will always stay last. I also skipped the header files of libpq and ecpg, in case people want to use those with older compilers. There were also a small number of cases where the enum type wasn't used anywhere (but the enum values were), which ended up confusing pgindent a bit, so I left those alone. Discussion: https://www.postgresql.org/message-id/flat/386f8c45-c8ac-4681-8add-e3b0852c1620%40eisentraut.org
* Prevent duplicate RTEPermissionInfo for plain-inheritance parentsAmit Langote2023-10-26
| | | | | | | | | | | | | | | | | | | Currently, expand_single_inheritance_child() doesn't reset perminfoindex in a plain-inheritance parent's child RTE, because prior to 387f9ed0a0, the executor would use the first child RTE to locate the parent's RTEPermissionInfo. That in turn causes add_rte_to_flat_rtable() to create an extra RTEPermissionInfo belonging to the parent's child RTE with the same content as the one belonging to the parent's original ("root") RTE. In 387f9ed0a0, we changed things so that the executor can now use the parent's "root" RTE for locating its RTEPermissionInfo instead of the child RTE, so the latter's perminfoindex need not be set anymore, so make it so. Reported-by: Tom Lane Discussion: https://postgr.es/m/839708.1698174464@sss.pgh.pa.us Backpatch-through: 16
* Fix problems when a plain-inheritance parent table is excluded.Tom Lane2023-10-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When an UPDATE/DELETE/MERGE's target table is an old-style inheritance tree, it's possible for the parent to get excluded from the plan while some children are not. (I believe this is only possible if we can prove that a CHECK ... NO INHERIT constraint on the parent contradicts the query WHERE clause, so it's a very unusual case.) In such a case, ExecInitModifyTable mistakenly concluded that the first surviving child is the target table, leading to at least two bugs: 1. The wrong table's statement-level triggers would get fired. 2. In v16 and up, it was possible to fail with "invalid perminfoindex 0 in RTE with relid nnnn" due to the child RTE not having permissions data included in the query plan. This was hard to reproduce reliably because it did not occur unless the update triggered some non-HOT index updates. In v14 and up, this is easy to fix by defining ModifyTable.rootRelation to be the parent RTE in plain inheritance as well as partitioned cases. While the wrong-triggers bug also appears in older branches, the relevant code in both the planner and executor is quite a bit different, so it would take a good deal of effort to develop and test a suitable patch. Given the lack of field complaints about the trigger issue, I'll desist for now. (Patching v11 for this seems unwise anyway, given that it will have no more releases after next month.) Per bug #18147 from Hans Buschmann. Amit Langote and Tom Lane Discussion: https://postgr.es/m/18147-6fc796538913ee88@postgresql.org
* Fix missed optimization in relation_excluded_by_constraints().Tom Lane2023-10-11
| | | | | | | | | | | | | | | | | | | | | | In commit 3fc6e2d7f, I (tgl) argued that we only need to check for a constant-FALSE restriction clause when there's exactly one restriction clause, on the grounds that const-folding would have thrown away anything ANDed with a Const FALSE. That's true just after const-folding has been applied, but subsequent processing such as equivalence class expansion could result in cases where a Const FALSE is ANDed with some other stuff. (Compare for instance joinrels.c's restriction_is_constant_false.) Hence, tweak this logic to check all the elements of the baserestrictinfo list, not just one; that's cheap enough to not be worth worrying about. There is one existing test case where this visibly improves the plan. There would not be any savings in runtime, but the planner effort and executor startup effort will be reduced, and anyway it's odd that we can detect related cases but not this one. Richard Guo (independently discovered by David Rowley) Discussion: https://postgr.es/m/CAMbWs4_x3-CnVVrCboS1LkEhB5V+W7sLSCabsRiG+n7+5_kqbg@mail.gmail.com
* Strip off ORDER BY/DISTINCT aggregate pathkeys in create_agg_pathDavid Rowley2023-10-09
| | | | | | | | | | | | | | | | | | | | | | | 1349d2790 added code to adjust the PlannerInfo.group_pathkeys so that ORDER BY / DISTINCT aggregate functions could obtain pre-sorted inputs to allow faster execution. That commit forgot to adjust the pathkeys in create_agg_path(). Some code in there assumed that it was always fine to make the AggPath's pathkeys the same as its subpath's. That seems to have been ok up until 1349d2790, but since that commit adds pathkeys for columns which are within the aggregate function, those columns won't be available above the aggregate node. This can result in "could not find pathkey item to sort" during create_plan(). The fix here is to strip off the additional pathkeys added by adjust_group_pathkeys_for_groupagg(). It seems that the pathkeys here will only ever be group_pathkeys, so all we need to do is check if the length of the pathkey list is longer than the num_groupby_pathkeys and get rid of the additional ones only if we see extras. Reported-by: Justin Pryzby Reviewed-by: Richard Guo Discussion: https://postgr.es/m/ZQhYYRhUxpW3PSf9%40telsasoft.com Backpatch-through: 16, where 1349d2790 was introduced
* Robustify find_base_rel and find_base_rel_ignore_joinDavid Rowley2023-09-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Improve find_base_rel() and find_base_rel_ignore_join() so that they raise an ERROR if they ever receive a negative relid value in non-cassert builds. If either of these functions had ever received a negative relid then they'd have attempted to access memory that does not belong to simple_rel_array. Because no evidence has been presented of actual cases where bugs have caused this to happen, here we take a lightweight approach to checking for negative values and simply cast both values to uint32 before performing the comparison. This will cause any negative relids to be seen as greater than simple_rel_array_size which will ERROR rather than attempt to access a negative simple_rel_array element. Obviously, the run-time error is better than a crash, so it makes sense to protect against this, especially when it can be done without adding any additional run-time overhead. There is a slight change here if the functions are ever called with a relid of 0. This will pass the bounds check, but that array entry should be NULL (along with the corresponding simple_rte_array entry), so won't pass the "if (rel)" condition and still fall through and raise an ERROR. Author: Ranier Vilela Reviewed-by: Ashutosh Bapat, David Rowley Discussion: https://postgr.es/m/CAEudQArQSghBu2gLojg4o_tnHj_x2HcS%3D%2BwewL3NJS8z0VnK%2Bg%40mail.gmail.com
* Catalog not-null constraintsAlvaro Herrera2023-08-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We now create contype='n' pg_constraint rows for not-null constraints. We propagate these constraints to other tables during operations such as adding inheritance relationships, creating and attaching partitions and creating tables LIKE other tables. We also spawn not-null constraints for inheritance child tables when their parents have primary keys. These related constraints mostly follow the well-known rules of conislocal and coninhcount that we have for CHECK constraints, with some adaptations: for example, as opposed to CHECK constraints, we don't match not-null ones by name when descending a hierarchy to alter it, instead matching by column name that they apply to. This means we don't require the constraint names to be identical across a hierarchy. For now, we omit them for system catalogs. Maybe this is worth reconsidering. We don't support NOT VALID nor DEFERRABLE clauses either; these can be added as separate features later (this patch is already large and complicated enough.) psql shows these constraints in \d+. pg_dump requires some ad-hoc hacks, particularly when dumping a primary key. We now create one "throwaway" not-null constraint for each column in the PK together with the CREATE TABLE command, and once the PK is created, all those throwaway constraints are removed. This avoids having to check each tuple for nullness when the dump restores the primary key creation. pg_upgrading from an older release requires a somewhat brittle procedure to create a constraint state that matches what would be created if the database were being created fresh in Postgres 17. I have tested all the scenarios I could think of, and it works correctly as far as I can tell, but I could have neglected weird cases. This patch has been very long in the making. The first patch was written by Bernd Helmle in 2010 to add a new pg_constraint.contype value ('n'), which I (Álvaro) then hijacked in 2011 and 2012, until that one was killed by the realization that we ought to use contype='c' instead: manufactured CHECK constraints. However, later SQL standard development, as well as nonobvious emergent properties of that design (mostly, failure to distinguish them from "normal" CHECK constraints as well as the performance implication of having to test the CHECK expression) led us to reconsider this choice, so now the current implementation uses contype='n' again. During Postgres 16 this had already been introduced by commit e056c557aef4, but there were some problems mainly with the pg_upgrade procedure that couldn't be fixed in reasonable time, so it was reverted. In 2016 Vitaly Burovoy also worked on this feature[1] but found no consensus for his proposed approach, which was claimed to be closer to the letter of the standard, requiring an additional pg_attribute column to track the OID of the not-null constraint for that column. [1] https://postgr.es/m/CAKOSWNkN6HSyatuys8xZxzRCR-KL1OkHS5-b9qd9bf1Rad3PLA@mail.gmail.com Author: Álvaro Herrera <alvherre@alvh.no-ip.org> Author: Bernd Helmle <mailings@oopsware.de> Reviewed-by: Justin Pryzby <pryzby@telsasoft.com> Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com> Reviewed-by: Dean Rasheed <dean.a.rasheed@gmail.com>
* Re-allow FDWs and custom scan providers to replace joins with pseudoconstant ↵Etsuro Fujita2023-08-15
| | | | | | | | | | | | | | | | | | | | | | | | | | quals. This was disabled in commit 6f80a8d9c due to the lack of support for handling of pseudoconstant quals assigned to replaced joins in createplan.c. To re-allow it, this patch adds the support by 1) modifying the ForeignPath and CustomPath structs so that if they represent foreign and custom scans replacing a join with a scan, they store the list of RestrictInfo nodes to apply to the join, as in JoinPaths, and by 2) modifying create_scan_plan() in createplan.c so that it uses that list in that case, instead of the baserestrictinfo list, to get pseudoconstant quals assigned to the join, as mentioned in the commit message for that commit. Important item for the release notes: this is non-backwards-compatible since it modifies the ForeignPath and CustomPath structs, as mentioned above, and changes the argument lists for FDW helper functions create_foreignscan_path(), create_foreign_join_path(), and create_foreign_upper_path(). Richard Guo, with some additional changes by me, reviewed by Nishant Sharma, Suraj Kharage, and Richard Guo. Discussion: https://postgr.es/m/CADrsxdbcN1vejBaf8a%2BQhrZY5PXL-04mCd4GDu6qm6FigDZd6Q%40mail.gmail.com
* Account for startup rows when costing WindowAggsDavid Rowley2023-08-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Here we adjust the costs for WindowAggs so that they properly take into account how much of their subnode they must read before outputting the first row. Without this, we always assumed that the startup cost for the WindowAgg was not much more expensive than the startup cost of its subnode, however, that's going to be completely wrong in many cases. The WindowAgg may have to read *all* of its subnode to output a single row with certain window bound options. Here we estimate how many rows we'll need to read from the WindowAgg's subnode and proportionally add more of the subnode's run costs onto the WindowAgg's startup costs according to how much of it we expect to have to read in order to produce the first WindowAgg row. The reason this is more important than we might have initially thought is that we may end up making use of a path from the lower planner that works well as a cheap startup plan when the query has a LIMIT clause, however, the WindowAgg might mean we need to read far more rows than what the LIMIT specifies. No backpatch on this so as not to cause plan changes in released versions. Bug: #17862 Reported-by: Tim Palmer Author: David Rowley Reviewed-by: Andy Fan Discussion: https://postgr.es/m/17862-1ab8f74b0f7b0611@postgresql.org Discussion: https://postgr.es/m/CAApHDvrB0S5BMv+0-wTTqWFE-BJ0noWqTnDu9QQfjZ2VSpLv_g@mail.gmail.com
* Disallow replacing joins with scans in problematic cases.Etsuro Fujita2023-07-28
| | | | | | | | | | | | | | | | | | | | | | | | Commit e7cb7ee14, which introduced the infrastructure for FDWs and custom scan providers to replace joins with scans, failed to add support handling of pseudoconstant quals assigned to replaced joins in createplan.c, leading to an incorrect plan without a gating Result node when postgres_fdw replaced a join with such a qual. To fix, we could add the support by 1) modifying the ForeignPath and CustomPath structs to store the list of RestrictInfo nodes to apply to the join, as in JoinPaths, if they represent foreign and custom scans replacing a join with a scan, and by 2) modifying create_scan_plan() in createplan.c to use that list in that case, instead of the baserestrictinfo list, to get pseudoconstant quals assigned to the join; but #1 would cause an ABI break. So fix by modifying the infrastructure to just disallow replacing joins with such quals. Back-patch to all supported branches. Reported by Nishant Sharma. Patch by me, reviewed by Nishant Sharma and Richard Guo. Discussion: https://postgr.es/m/CADrsxdbcN1vejBaf8a%2BQhrZY5PXL-04mCd4GDu6qm6FigDZd6Q%40mail.gmail.com
* Fix calculation of relid sets for partitionwise child joins.Tom Lane2023-07-21
| | | | | | | | | | | | | | | | | | | Applying add_outer_joins_to_relids() to a child join doesn't actually work, even if we've built a SpecialJoinInfo specialized to the child, because that function will also compare the join's relids to elements of the main join_info_list, which only deal in regular relids not child relids. This mistake escaped detection by the existing partitionwise join tests because they didn't test any cases where add_outer_joins_to_relids() needs to add additional OJ relids (that is, any cases where join reordering per identity 3 is possible). Instead, let's apply adjust_child_relids() to the relids of the parent join. This requires minor code reordering to collect the relevant AppendRelInfo structures first, but that's work we'd do shortly anyway. Report and fix by Richard Guo; cosmetic changes by me Discussion: https://postgr.es/m/CAMbWs49NCNbyubZWgci3o=_OTY=snCfAPtMnM-32f3mm-K-Ckw@mail.gmail.com
* Allow plan nodes with initPlans to be considered parallel-safe.Tom Lane2023-07-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the plan itself is parallel-safe, and the initPlans are too, there's no reason anymore to prevent the plan from being marked parallel-safe. That restriction (dating to commit ab77a5a45) was really a special case of the fact that we couldn't transmit subplans to parallel workers at all. We fixed that in commit 5e6d8d2bb and follow-ons, but this case never got addressed. We still forbid attaching initPlans to a Gather node that's inserted pursuant to debug_parallel_query = regress. That's because, when we hide the Gather from EXPLAIN output, we'd hide the initPlans too, causing cosmetic regression diffs. It seems inadvisable to kluge EXPLAIN to the extent required to make the output look the same, so just don't do it in that case. Along the way, this also takes care of some sloppiness about updating path costs to match when we move initplans from one place to another during createplan.c and setrefs.c. Since all the planning decisions are already made by that point, this is just cosmetic; but it seems good to keep EXPLAIN output consistent with where the initplans are. The diff in query_planner() might be worth remarking on. I found that one because after fixing things to allow parallel-safe initplans, one partition_prune test case changed plans (as shown in the patch) --- but only when debug_parallel_query was active. The reason proved to be that we only bothered to mark Result nodes as potentially parallel-safe when debug_parallel_query is on. This neglects the fact that parallel-safety may be of interest for a sub-query even though the Result itself doesn't parallelize. Discussion: https://postgr.es/m/1129530.1681317832@sss.pgh.pa.us
* Don't include CaseTestExpr in JsonValueExpr.formatted_exprAmit Langote2023-07-13
| | | | | | | | | | | | | | | | | | | | | | | | A CaseTestExpr is currently being put into JsonValueExpr.formatted_expr as placeholder for the result of evaluating JsonValueExpr.raw_expr, which in turn is evaluated separately. Though, there's no need for this indirection if raw_expr itself can be embedded into formatted_expr and evaluated as part of evaluating the latter, especially as there is no special reason to evaluate it separately. So this commit makes it so. As a result, JsonValueExpr.raw_expr no longer needs to be evaluated in ExecInterpExpr(), eval_const_exprs_mutator() etc. and is now only used for displaying the original "unformatted" expression in ruleutils.c. While at it, this also removes the function makeCaseTestExpr(), because the code in makeJsonConstructorExpr() looks more readable without it IMO and isn't used by anyone else either. Finally, a note is added in the comment above CaseTestExpr's definition that JsonConstructorExpr is also using it. Reviewed-by: Álvaro Herrera <alvherre@alvh.no-ip.org> Discussion: https://postgr.es/m/CA+HiwqE4XTdfb1nW=Ojoy_tQSRhYt-q_kb6i5d4xcKyrLC1Nbg@mail.gmail.com
* Centralize fixups for mismatched nullingrels in nestloop params.Tom Lane2023-06-20
| | | | | | | | | | | | | | | | | | | | It turns out that the fixes we applied in commits bfd332b3f and 63e4f13d2 were not nearly enough to solve the problem. We'd focused narrowly on subquery RTEs with lateral references, but lateral references can occur in several other RTE kinds such as function RTEs. Putting the same hack into half a dozen code paths seems quite unattractive. Hence, revert the code changes (but not the test cases) from those commits and instead solve it centrally in identify_current_nestloop_params(), as Richard proposed originally. This is a bit annoying because it could mask erroneous nullingrels in nestloop params that are generated from non-LATERAL parameterized paths; but on balance I don't see a better way. Maybe at some future time we'll be motivated to find a more rigorous approach to nestloop params, but that's not happening for beta2. Richard Guo and Tom Lane Discussion: https://postgr.es/m/CAMbWs48Jcw-NvnxT23WiHP324wG44DvzcH1j4hc0Zn+3sR9cfg@mail.gmail.com
* Fix "wrong varnullingrels" for subquery nestloop parameters.Tom Lane2023-06-12
| | | | | | | | | | | | | | | If we apply outer join identity 3 when relation C is a subquery having lateral references to relation B, then the lateral references within C continue to bear the original syntactically-correct varnullingrels marks, but that won't match what is available from the outer side of the nestloop. Compensate for that in process_subquery_nestloop_params(). This is a slightly hacky fix, but we certainly don't want to re-plan C in toto for each possible outer join order, so there's not a lot of better alternatives. Richard Guo and Tom Lane, per report from Markus Winand Discussion: https://postgr.es/m/DFBB2D25-DE97-49CA-A60E-07C881EA59A7@winand.at
* nbtree: Allocate new pages in separate function.Peter Geoghegan2023-06-10
| | | | | | | | | | | | | | | | | | | | | | | | Split nbtree's _bt_getbuf function is two: code that read locks or write locks existing pages remains in _bt_getbuf, while code that deals with allocating new pages is moved to a new, dedicated function called _bt_allocbuf. This simplifies most _bt_getbuf callers, since it is no longer necessary for them to pass a heaprel argument. Many of the changes to nbtree from commit 61b313e4 can be reverted. This minimizes the divergence between HEAD/PostgreSQL 16 and earlier release branches. _bt_allocbuf replaces the previous nbtree idiom of passing P_NEW to _bt_getbuf. There are only 3 affected call sites, all of which continue to pass a heaprel for recovery conflict purposes. Note that nbtree's use of P_NEW was superficial; nbtree never actually relied on the P_NEW code paths in bufmgr.c, so this change is strictly mechanical. GiST already took the same approach; it has a dedicated function for allocating new pages called gistNewBuffer(). That factor allowed commit 61b313e4 to make much more targeted changes to GiST. Author: Peter Geoghegan <pg@bowt.ie> Reviewed-By: Heikki Linnakangas <hlinnaka@iki.fi> Discussion: https://postgr.es/m/CAH2-Wz=8Z9qY58bjm_7TAHgtW6RzZ5Ke62q5emdCEy9BAzwhmg@mail.gmail.com
* Fix filtering of "cloned" outer-join quals some more.Tom Lane2023-05-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | We've had multiple issues with the clause_is_computable_at logic that I introduced in 2489d76c4: it's been known to accept more than one clone of the same qual at the same plan node, and also to accept no clones at all. It's looking impractical to get it 100% right on the basis of the currently-stored information, so fix it by introducing a new RestrictInfo field "incompatible_relids" that explicitly shows which outer joins a given clone mustn't be pushed above. In principle we could populate this field in every RestrictInfo, but that would cost space and there doesn't presently seem to be a need for it in general. Also, while deconstruct_distribute_oj_quals can easily fill the field with the remaining members of the commutative join set that it's considering, computing it in the general case seems again pretty complicated. So for now, just fill it for clone quals. Along the way, fix a bug that may or may not be only latent: equivclass.c was generating replacement clauses with is_pushed_down and has_clone/is_clone markings that didn't match their required_relids. This led me to conclude that leaving the clone flags out of make_restrictinfo's purview wasn't such a great idea after all, so add them. Per report from Richard Guo. Discussion: https://postgr.es/m/CAMbWs48EYi_9-pSd0ORes1kTmTeAjT4Q3gu49hJtYCbSn2JyeA@mail.gmail.com