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
This will ease a follow-up move that will generate automatically this code. The C file is renamed, for consistency with the node-related files whose code are generated by gen_node_support.pl: - queryjumble.c -> queryjumblefuncs.c - utils/queryjumble.h -> nodes/queryjumble.h Per a suggestion from Peter Eisentraut. Reviewed-by: Peter Eisentraut Discussion: https://postgr.es/m/Y5BHOUhX3zTH/ig6@paquier.xyz
Postgres' standard mechanism for reporting errors (ereport() or elog()) is used for all sorts of error conditions. This means that throwing an exception via ereport(ERROR) requires an expensive transaction or subtransaction abort and cleanup, since the exception catcher dare not make many assumptions about what has gone wrong. There are situations where we would rather have a lighter-weight mechanism for dealing with errors that are known to be safe to recover from without a full transaction cleanup. This commit creates infrastructure to let us adapt existing error-reporting code for that purpose. See the included documentation changes for details. Follow-on commits will provide test code and usage examples. The near-term plan is to convert most if not all datatype input functions to report invalid input "softly". This will enable implementing some SQL/JSON features cleanly and without the cost of subtransactions, and it will also allow creating COPY options to deal with bad input without cancelling the whole COPY. This patch is mostly by me, but it owes very substantial debt to earlier work by Nikita Glukhov, Andrew Dunstan, and Amul Sul. Thanks also to Andres Freund for review. Discussion: https://postgr.es/m/3bbbb0df-7382-bf87-9737-340ba096e034@postgrespro.ru
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
Add a NodeTag field to struct Bitmapset. This is free because of alignment considerations on 64-bit hardware. While it adds some space on 32-bit machines, we aren't optimizing for that case anymore. The advantage is that data structures such as Lists of Bitmapsets are now first-class objects to the Node infrastructure, and don't require special-case code to handle. This patch includes removal of one such special case, in indxpath.c: bms_equal_any() can now be replaced by list_member(). There may be more existing code that could be simplified, but I didn't look very hard. We also get to drop the read_write_ignore annotations on a couple of RelOptInfo fields. The outfuncs/readfuncs support is arranged so that nothing changes in the string representation of a Bitmapset field; therefore, this doesn't need a catversion bump. Amit Langote and Tom Lane Discussion: https://postgr.es/m/109089.1668197158@sss.pgh.pa.us
Per a question from Andres Freund. While here, also make the list of nodetag-only files easier to compare to the full list of input files. Discussion: https://postgr.es/m/20220710214622.haiektrjzisob6rl@awork3.anarazel.de
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
When maintaining or merging patches, one of the most common sources for conflicts are the list of objects in makefiles. Especially when the split across lines has been changed on both sides, which is somewhat common due to attempting to stay below 80 columns, those conflicts are unnecessarily laborious to resolve. By splitting, and alphabetically sorting, OBJS style lines into one object per line, conflicts should be less frequent, and easier to resolve when they still occur. Author: Andres Freund Discussion: https://postgr.es/m/20191029200901.vww4idgcxv74cwes@alap3.anarazel.de
An extensible node is always tagged T_Extensible, but the extnodename field identifies it more specifically; it may also include arbitrary private data. Extensible nodes can be copied, tested for equality, serialized, and deserialized, but the core system doesn't know anything about them otherwise. Some extensions may find it useful to include these nodes in fdw_private or custom_private lists in lieu of arm-wrestling their data into a format that the core code can understand. Along the way, so as not to burden the authors of such extensible node types too much, expose the functions for writing serialized tokens, and for serializing and deserializing bitmapsets. KaiGai Kohei, per a design suggested by me. Reviewed by Andres Freund and by me, and further edited by me.