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2024-08-01Convert node test compile-time settings into run-time parametersPeter Eisentraut
This converts COPY_PARSE_PLAN_TREES WRITE_READ_PARSE_PLAN_TREES RAW_EXPRESSION_COVERAGE_TEST into run-time parameters debug_copy_parse_plan_trees debug_write_read_parse_plan_trees debug_raw_expression_coverage_test They can be activated for tests using PG_TEST_INITDB_EXTRA_OPTS. The compile-time symbols are kept for build farm compatibility, but they now just determine the default value of the run-time settings. Furthermore, support for these settings is not compiled in at all unless assertions are enabled, or the new symbol DEBUG_NODE_TESTS_ENABLED is defined at compile time, or any of the legacy compile-time setting symbols are defined. So there is no run-time overhead in production builds. (This is similar to the handling of DISCARD_CACHES_ENABLED.) Discussion: https://www.postgresql.org/message-id/flat/30747bd8-f51e-4e0c-a310-a6e2c37ec8aa%40eisentraut.org
2023-03-22Fix make maintainer-clean with queryjumblefuncs.*.c files in src/backend/nodes/Michael Paquier
The files generated by gen_node_support.pl for query jumbling (queryjumblefuncs.funcs.c and queryjumblefuncs.switch.c) were not being removed on make maintainer-clean (they need to remain around after a simple "clean"). This commit makes the operation consistent with the copy, equal, out and read files. While on it, update a comment in the nodes'README where a reference to queryjumblefuncs.funcs.c was missing. Reported-by: Nathan Bossart Reviewed-by: Richard Guo, Daniel Gustafsson Discussion: https://postgr.es/m/ZBgAfTHcL6W7zGdW@paquier.xyz
2023-01-31Generate code for query jumbling through gen_node_support.plMichael Paquier
This commit changes the query jumbling code in queryjumblefuncs.c to be generated automatically based on the information of the nodes in the headers of src/include/nodes/ by using gen_node_support.pl. This approach offers many advantages: - Support for query jumbling for all the utility statements, based on the state of their parsed Nodes and not only their query string. This will greatly ease the switch to normalize the information of some DDLs, like SET or CALL for example (this is left unchanged and should be part of a separate discussion). With this feature, the number of entries stored for utilities in pg_stat_statements is reduced (for example now "CHECKPOINT" and "checkpoint" mean the same thing with the same query ID). - Documentation of query jumbling directly in the structure definition of the nodes. Since this code has been introduced in pg_stat_statements and then moved to code, the reasons behind the choices of what should be included in the jumble are rather sparse. Note that some explanation is added for the most relevant parts, as a start. - Overall code reduction and more consistency with the other parts generating read, write and copy depending on the nodes. The query jumbling is controlled by a couple of new node attributes, documented in nodes/nodes.h: - custom_query_jumble, to mark a Node as having a custom implementation. - no_query_jumble, to ignore entirely a Node. - query_jumble_ignore, to ignore a field in a Node. - query_jumble_location, to mark a location in a Node, for normalization. This can apply only to int fields, with "location" in their name (only Const as of this commit). There should be no compatibility impact on pg_stat_statements, as the new code applies the jumbling to the same fields for each node (its regression tests have no modification, for one). Some benchmark of the query jumbling between HEAD and this commit for SELECT and DMLs has proved that this new code does not cause a performance regression, with computation times close for both methods. For utility queries, the new method is slower than the previous method of calculating a hash of the query string, though we are talking about extra ns-level changes based on what I measured, which is unnoticeable even for OLTP workloads as a query ID is calculated once per query post-parse analysis. Author: Michael Paquier Reviewed-by: Peter Eisentraut Discussion: https://postgr.es/m/Y5BHOUhX3zTH/ig6@paquier.xyz
2022-11-16Invent "multibitmapsets", and use them to speed up antijoin detection.Tom Lane
Implement a data structure that is a List of Bitmapsets, which is essentially a 2-D boolean array except that the rows need not all be the same width. Operations such as union and intersection are meaningful for these, just as they are for Bitmapsets. Eventually we might build many of the same operations that we have written for Bitmapsets, but for the first use-case we just need a few. That first use-case is for antijoin detection: reduce_outer_joins needs to find the set of Vars that are certain to be non-null in a successfully joined (not null-extended) left join row, and also find the set of Vars subject to higher-level IS NULL constraints, and intersect them. We had been doing this by making Lists of the Var nodes and then using list_intersect, which works but is pretty inefficient compared to a bitmapset-like intersection. Potentially it's O(N^2) if there are a lot of Vars involved, which fortunately there generally aren't; still it's not great. Moreover, that method requires the Vars of interest to be exactly equal() in the join condition and the upper IS NULL condition, which is problematic for my WIP patch that labels Vars according to which outer joins have possibly nulled them. Discussion: https://postgr.es/m/892228.1668437838@sss.pgh.pa.us Discussion: https://postgr.es/m/CAMbWs4-mvPPCJ1W6iK6dD5HiNwoJdi6mZp=-7mE8N9Sh+cd0tQ@mail.gmail.com
2022-07-09Doc: rearrange high-level commentary about node support coverage.Tom Lane
copyfuncs.c and friends no longer seem like great places to put high-level remarks about what's covered and what isn't. Move that material to backend/nodes/README and other more-prominent places. Add back (versions of) some remarks that disappeared in 2be87f092. Discussion: https://postgr.es/m/3843645.1657385930@sss.pgh.pa.us
2022-07-09Automatically generate node support functionsPeter Eisentraut
Add a script to automatically generate the node support functions (copy, equal, out, and read, as well as the node tags enum) from the struct definitions. For each of the four node support files, it creates two include files, e.g., copyfuncs.funcs.c and copyfuncs.switch.c, to include in the main file. All the scaffolding of the main file stays in place. I have tried to mostly make the coverage of the output match what is currently there. For example, one could now do out/read coverage of utility statement nodes, but I have manually excluded those for now. The reason is mainly that it's easier to diff the before and after, and adding a bunch of stuff like this might require a separate analysis and review. Subtyping (TidScan -> Scan) is supported. For the hard cases, you can just write a manual function and exclude generating one. For the not so hard cases, there is a way of annotating struct fields to get special behaviors. For example, pg_node_attr(equal_ignore) has the field ignored in equal functions. (In this patch, I have only ifdef'ed out the code to could be removed, mainly so that it won't constantly have merge conflicts. It will be deleted in a separate patch. All the code comments that are worth keeping from those sections have already been moved to the header files where the structs are defined.) Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://www.postgresql.org/message-id/flat/c1097590-a6a4-486a-64b1-e1f9cc0533ce%40enterprisedb.com
2021-09-09Remove Value node structPeter Eisentraut
The Value node struct is a weird construct. It is its own node type, but most of the time, it actually has a node type of Integer, Float, String, or BitString. As a consequence, the struct name and the node type don't match most of the time, and so it has to be treated specially a lot. There doesn't seem to be any value in the special construct. There is very little code that wants to accept all Value variants but nothing else (and even if it did, this doesn't provide any convenient way to check it), and most code wants either just one particular node type (usually String), or it accepts a broader set of node types besides just Value. This change removes the Value struct and node type and replaces them by separate Integer, Float, String, and BitString node types that are proper node types and structs of their own and behave mostly like normal node types. Also, this removes the T_Null node tag, which was previously also a possible variant of Value but wasn't actually used outside of the Value contained in A_Const. Replace that by an isnull field in A_Const. Reviewed-by: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org> Reviewed-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com> Discussion: https://www.postgresql.org/message-id/flat/5ba6bc5b-3f95-04f2-2419-f8ddb4c046fb@enterprisedb.com
2019-01-29Rename nodes/relation.h to nodes/pathnodes.h.Tom Lane
The old name of this file was never a very good indication of what it was for. Now that there's also access/relation.h, we have a potential confusion hazard as well, so let's rename it to something more apropos. Per discussion, "pathnodes.h" is reasonable, since a good fraction of the file is Path node definitions. While at it, tweak a couple of other headers that were gratuitously importing relation.h into modules that don't need it. Discussion: https://postgr.es/m/7719.1548688728@sss.pgh.pa.us
2016-06-03Fix various common mispellings.Greg Stark
Mostly these are just comments but there are a few in documentation and a handful in code and tests. Hopefully this doesn't cause too much unnecessary pain for backpatching. I relented from some of the most common like "thru" for that reason. The rest don't seem numerous enough to cause problems. Thanks to Kevin Lyda's tool https://pypi.python.org/pypi/misspellings
2010-11-23Remove useless whitespace at end of linesPeter Eisentraut
2010-09-20Remove cvs keywords from all files.Magnus Hagander
2008-08-25Move exprType(), exprTypmod(), expression_tree_walker(), and related routinesTom Lane
into nodes/nodeFuncs, so as to reduce wanton cross-subsystem #includes inside the backend. There's probably more that should be done along this line, but this is a start anyway.
2008-03-20Make source code READMEs more consistent. Add CVS tags to all README files.Bruce Momjian
2003-11-29make sure the $Id tags are converted to $PostgreSQL as well ...PostgreSQL Daemon
1996-07-09Postgres95 1.01 Distribution - Virgin SourcesPG95-1_01Marc G. Fournier