3 Commits (758479213d574d6e2fbbdfee5328edef3d60da61)

Author	SHA1	Message	Date
Michael Paquier	bee23ea4dd	Show sizes of FETCH queries as constants in pg_stat_statements ... Prior to this patch, every FETCH call would generate a unique queryId with a different size specified. Depending on the workloads, this could lead to a significant bloat in pg_stat_statements, as repeatedly calling a specific cursor would result in a new queryId each time. For example, FETCH 1 c1; and FETCH 2 c1; would produce different queryIds. This patch improves the situation by normalizing the fetch size, so as semantically similar statements generate the same queryId. As a result, statements like the below, which differ syntactically but have the same effect, will now share a single queryId: FETCH FROM c1 FETCH NEXT c1 FETCH 1 c1 In order to do a normalization based on the keyword used in FETCH, FetchStmt is tweaked with a new FetchDirectionKeywords. This matters for "howMany", which could be set to a negative value depending on the direction, and we want to normalize the queries with enough information about the direction keywords provided, including RELATIVE, ABSOLUTE or all the ALL variants. Author: Sami Imseih <samimseih@gmail.com> Discussion: https://postgr.es/m/CAA5RZ0tA6LbHCg2qSS+KuM850BZC_+ZgHV7Ug6BXw22TNyF+MA@mail.gmail.com	6 months ago
Alexander Korotkov	6ab1dbd26b	Add NOT NULL checking of pg_stat_statements_reset() in tests ... This is preliminary patch. It adds NOT NULL checking for the result of pg_stat_statements_reset() function. It is needed for upcoming patch "Track statement entry timestamp" that will change the result type of this function to the timestamp of a reset performed. Discussion: https://postgr.es/m/flat/72e80e7b160a6eb189df9ef6f068cce3765d37f8.camel%40moonset.ru Author: Andrei Zubkov Reviewed-by: Julien Rouhaud, Hayato Kuroda, Yuki Seino, Chengxi Sun Reviewed-by: Anton Melnikov, Darren Rush, Michael Paquier, Sergei Kornilov Reviewed-by: Alena Rybakina, Andrei Lepikhov	2 years ago
Michael Paquier	de2aca2885	Expand regression tests of pg_stat_statements for utility queries ... This commit adds more coverage for utility statements so as it is possible to track down all the effects of query normalization done for all the queries that use either Const or A_Const nodes, which are the nodes where normalization makes the most sense as they apply to constants (well, most of the time, really). This set of queries is extracted from an analysis done while looking at full dumps of the regression database when applying different levels of normalization to either Const or A_Const nodes for utilities, as of a minimal set of these, for: - All relkinds (CREATE, ALTER, DROP) - Policies - Cursors - Triggers - Types - Rules - Statistics - CALL - Transaction statements (isolation level, options) - EXPLAIN - COPY Note that pg_stat_statements is not switched yet to show any normalization for utilities, still it improves the default coverage of the query jumbling code (not by as much as enabling query jumbling on the main regression test suite, though): - queryjumblefuncs.funcs.c: 36.8% => 48.5% - queryjumblefuncs.switch.c: 33.2% => 43.1% Reviewed-by: Bertrand Drouvot Discussion: https://postgr.es/m/Y+MRdEq9W9XVa2AB@paquier.xyz	3 years ago