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13 daysUse more palloc_object() and palloc_array() in contrib/Michael Paquier
The idea is to encourage more the use of these new routines across the tree, as these offer stronger type safety guarantees than palloc(). In an ideal world, palloc() would then act as an internal routine of these flavors, whose footprint in the tree is minimal. The patch sent by the author is very large, and this chunk of changes represents something like 10% of the overall patch submitted. The code compiled is the same before and after this commit, using objdump to do some validation with a difference taken in-between. There are some diffs, which are caused by changes in line numbers because some of the new allocation formulas are shorter, for the following files: trgm_regexp.c, xpath.c and pg_walinspect.c. Author: David Geier <geidav.pg@gmail.com> Discussion: https://postgr.es/m/ad0748d4-3080-436e-b0bc-ac8f86a3466a@gmail.com
2025-09-23Keep track of what RTIs a Result node is scanning.Robert Haas
Result nodes now include an RTI set, which is only non-NULL when they have no subplan, and is taken from the relid set of the RelOptInfo that the Result is generating. ExplainPreScanNode now takes notice of these RTIs, which means that a few things get schema-qualified in the regression tests that previously did not. This makes the output more consistent between cases where some part of the plan tree is replaced by a Result node and those where this does not happen. Likewise, pg_overexplain's EXPLAIN (RANGE_TABLE) now displays the RTIs stored in a Result node just as it already does for other RTI-bearing node types. Result nodes also now include a result_reason, which tells us something about why the Result node was inserted. Using that information, EXPLAIN now emits, where relevant, a "Replaces" line describing the origin of a Result node. The purpose of these changes is to allow code that inspects a Plan tree to understand the origin of Result nodes that appear therein. Discussion: http://postgr.es/m/CA+TgmoYeUZePZWLsSO+1FAN7UPePT_RMEZBKkqYBJVCF1s60=w@mail.gmail.com Reviewed-by: Alexandra Wang <alexandra.wang.oss@gmail.com> Reviewed-by: Richard Guo <guofenglinux@gmail.com> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: Junwang Zhao <zhjwpku@gmail.com>
2025-06-12Revert support for improved tracking of nested queriesMichael Paquier
This commit reverts the two following commits: - 499edb09741b, track more precisely query locations for nested statements. - 06450c7b8c70, a follow-up fix of 499edb09741b with query locations. The test introduced in this commit is not reverted. This is proving useful to track a problem that only pgaudit was able to detect. These prove to have issues with the tracking of SELECT statements, when these use multiple parenthesis which is something supported by the grammar. Incorrect location and lengths are causing pg_stat_statements to become confused, failing its job in query normalization with potential out-of-bound writes because the location and the length may not match with what can be handled. A lot of the query patterns discussed when this issue was reported have no test coverage in the main regression test suite, or the recovery test 027_stream_regress.pl would have caught the problems as pg_stat_statements is loaded by the node running the regression tests. A first step would be to improve the test coverage to stress more the query normalization logic. A different portion of this work was done in 45e0ba30fc40, with the addition of tests for nested queries. These can be left in the tree. They are useful to track the way inner queries are currently tracked by PGSS with non-top-level entries, and will be useful when reconsidering in the future the work reverted here. Reported-by: Alexander Kozhemyakin <a.kozhemyakin@postgrespro.ru> Discussion: https://postgr.es/m/18947-cdd2668beffe02bf@postgresql.org
2025-05-21Fix regression with location calculation of nested statementsMichael Paquier
The statement location calculated for some nested query cases was wrong when multiple queries are sent as a single string, these being separated by semicolons. As pointed by Sami Imseih, the location calculation was incorrect when the last query of nested statement with multiple queries does **NOT** finish with a semicolon for the last statement. In this case, the statement length tracked by RawStmt is 0, which is equivalent to say that the string should be used until its end. The code previously discarded this case entirely, causing the location to remain at 0, the same as pointing at the beginning of the string. This caused pg_stat_statements to store incorrect query strings. This issue has been introduced in 499edb09741b. I have looked at the diffs generated by pgaudit back then, and noticed the difference generated for this nested query case, but I have missed the point that it was an actual regression with an existing case. A test case is added in pg_stat_statements to provide some coverage, restoring the pre-17 behavior for the calculation of the query locations. Special thanks to David Steele, who, through an analysis of the test diffs generated by pgaudit with the new v18 logic, has poked me about the fact that my original analysis of the matter was wrong. The test output of pg_overexplain is updated to reflect the new logic, as the new locations refer to the beginning of the argument passed to the function explain_filter(). When the module was introduced in 8d5ceb113e3f, which was after 499edb09741b (for the new calculation method), the locations of the test were not actually right: the plan generated for the query string given in input of the function pointed to the top-level query, not the nested one. Reported-by: David Steele <david@pgbackrest.org> Author: Michael Paquier <michael@paquier.xyz> Reviewed-by: Anthonin Bonnefoy <anthonin.bonnefoy@datadoghq.com> Reviewed-by: Jian He <jian.universality@gmail.com> Reviewed-by: Sami Imseih <samimseih@gmail.com> Reviewed-by: David Steele <david@pgbackrest.org> Discussion: https://postgr.es/m/844a3b38-bbf1-4fb2-9fd6-f58c35c09917@pgbackrest.org
2025-04-19Fix typos and grammar in the codeMichael Paquier
The large majority of these have been introduced by recent commits done in the v18 development cycle. Author: Alexander Lakhin <exclusion@gmail.com> Discussion: https://postgr.es/m/9a7763ab-5252-429d-a943-b28941e0e28b@gmail.com
2025-04-12Harmonize function parameter names for Postgres 18.Peter Geoghegan
Make sure that function declarations use names that exactly match the corresponding names from function definitions in a few places. These inconsistencies were all introduced during Postgres 18 development. This commit was written with help from clang-tidy, by mechanically applying the same rules as similar clean-up commits (the earliest such commit was commit 035ce1fe).
2025-04-10Improve various new-to-v18 appendStringInfo callsDavid Rowley
Similar to 8461424fd, here we adjust a few new locations which were not using the most suitable appendStringInfo* function for the intended purpose. Author: David Rowley <drowleyml@gmail.com Discussion: https://postgr.es/m/CAApHDvqJnNjueb=Eoj8K+8n0g7nj_AcPWSiCj5RNV4fDejAfqA@mail.gmail.com
2025-03-28pg_overexplain: Use PG_MODULE_MAGIC_EXT.Robert Haas
I committed this contrib module just after Tom committed 55527368bd07248e91e3d37a782bf66b76f06865; adjust it to match. Author: Man Zeng <zengman@halodbtech.com> Discussion: http://postgr.es/m/174313513707.60295.16516085012903412705.pgcf@coridan.postgresql.org
2025-03-28pg_overexplain: Call previous hooks as appropriate.Robert Haas
It makes no sense to remember the previous values of the hook variables and then never bother calling those functions. Thanks to Andrei for spotting my goof. Author: Andrei Lepikhov <lepihov@gmail.com> Discussion: http://postgr.es/m/41a344e3-ffb1-4296-8ba7-801f1e9642e5@gmail.com
2025-03-27pg_overexplain: Filter out actual row count from test result.Robert Haas
Per buildfarm, these are not stable. In particular, 1/8 is sometimes 0.12 and sometimes 0.13.
2025-03-26pg_overexplain: SET jit=off when running tests.Robert Haas
Per buildfarm.
2025-03-26Fix oversights in commit 8d5ceb113e3f7ddb627bd40b26438a9d2fa05512Robert Haas
It added bogus whitespace at the end of a line in the documentation. It should not have done that. The pg_overexplain tests must SET debug_parallel_query = false, not just RESET debug_parallel_query, or we get failures on test machines that make debug_parallel_query = true the defualt.
2025-03-26pg_overexplain: Additional EXPLAIN options for debugging.Robert Haas
There's a fair amount of information in the Plan and PlanState trees that isn't printed by any existing EXPLAIN option. This means that, when working on the planner, it's often necessary to rely on facilities such as debug_print_plan, which produce excessively voluminous output. Hence, use the new EXPLAIN extension facilities to implement EXPLAIN (DEBUG) and EXPLAIN (RANGE_TABLE) as extensions to the core EXPLAIN facility. A great deal more could be done here, and the specific choices about what to print and how are definitely arguable, but this is at least a starting point for discussion and a jumping-off point for possible future improvements. Reviewed-by: Sami Imseih <samimseih@gmail.com> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Reviweed-by: Andrei Lepikhov <lepihov@gmail.com> (who didn't like it) Discussion: http://postgr.es/m/CA+TgmoZfvQUBWQ2P8iO30jywhfEAKyNzMZSR+uc2xr9PZBw6eQ@mail.gmail.com