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499edb0974
Previously, a Query generated through the transform phase would have unset stmt_location, tracking the starting point of a query string. Extensions relying on the statement location to extract its relevant parts in the source text string would fallback to use the whole statement instead, leading to confusing results like in pg_stat_statements for queries relying on nested queries, like: - EXPLAIN, with top-level and nested query using the same query string, and a query ID coming from the nested query when the non-top-level entry. - Multi-statements, with only partial portions of queries being normalized. - COPY TO with a query, SELECT or DMLs. This patch improves things by keeping track of the statement locations and propagate it to Query during transform, allowing PGSS to only show the relevant part of the query for nested query. This leads to less bloat in entries for non-top-level entries, as queries can now be grouped within the same (toplevel, queryid) duos in pg_stat_statements. The result gives a stricter one-one mapping between query IDs and its query strings. The regression tests introduced in 45e0ba30fc40 produce differences reflecting the new logic. Author: Anthonin Bonnefoy Reviewed-by: Michael Paquier, Jian He Discussion: https://postgr.es/m/CAO6_XqqM6S9bQ2qd=75W+yKATwoazxSNhv5sjW06fjGAtHbTUA@mail.gmail.com
32 lines
925 B
SQL
32 lines
925 B
SQL
--
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-- Information related to planning
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--
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-- These tests require track_planning to be enabled.
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SET pg_stat_statements.track_planning = TRUE;
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SELECT pg_stat_statements_reset() IS NOT NULL AS t;
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--
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-- [re]plan counting
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--
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CREATE TABLE stats_plan_test ();
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PREPARE prep1 AS SELECT COUNT(*) FROM stats_plan_test;
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EXECUTE prep1;
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EXECUTE prep1;
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EXECUTE prep1;
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ALTER TABLE stats_plan_test ADD COLUMN x int;
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EXECUTE prep1;
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SELECT 42;
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SELECT 42;
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SELECT 42;
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SELECT plans, calls, rows, query FROM pg_stat_statements
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WHERE query NOT LIKE 'SELECT COUNT%' ORDER BY query COLLATE "C";
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-- for the prepared statement we expect at least one replan, but cache
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-- invalidations could force more
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SELECT plans >= 2 AND plans <= calls AS plans_ok, calls, rows, query FROM pg_stat_statements
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WHERE query LIKE 'SELECT COUNT%' ORDER BY query COLLATE "C";
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-- Cleanup
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DROP TABLE stats_plan_test;
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SELECT pg_stat_statements_reset() IS NOT NULL AS t;
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