16 Commits (b18c2decd76eeffbd483c041c02bb0fb01b0f124)

Author	SHA1	Message	Date
David Rowley	2d0bbedda7	Rename shadowed local variables ... In a similar effort to f01592f91, here we mostly rename shadowed local variables to remove the warnings produced when compiling with -Wshadow=compatible-local. This fixes 63 warnings and leaves just 5. Author: Justin Pryzby, David Rowley Reviewed-by: Justin Pryzby Discussion https://postgr.es/m/20220817145434.GC26426%40telsasoft.com	3 years ago
Peter Eisentraut	9fd45870c1	Replace many MemSet calls with struct initialization ... This replaces all MemSet() calls with struct initialization where that is easily and obviously possible. (For example, some cases have to worry about padding bits, so I left those.) (The same could be done with appropriate memset() calls, but this patch is part of an effort to phase out MemSet(), so it doesn't touch memset() calls.) Reviewed-by: Ranier Vilela <ranier.vf@gmail.com> Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org> Discussion: https://www.postgresql.org/message-id/9847b13c-b785-f4e2-75c3-12ec77a3b05c@enterprisedb.com	3 years ago
Bruce Momjian	27b77ecf9f	Update copyright for 2022 ... Backpatch-through: 10	4 years ago
Peter Eisentraut	37b2764593	Some RELKIND macro refactoring ... Add more macros to group some RELKIND_* macros: - RELKIND_HAS_PARTITIONS() - RELKIND_HAS_TABLESPACE() - RELKIND_HAS_TABLE_AM() Reviewed-by: Michael Paquier <michael@paquier.xyz> Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org> Discussion: https://www.postgresql.org/message-id/flat/a574c8f1-9c84-93ad-a9e5-65233d6fc00f%40enterprisedb.com	4 years ago
Bruce Momjian	ca3b37487b	Update copyright for 2021 ... Backpatch-through: 9.5	5 years ago
Bruce Momjian	7559d8ebfa	Update copyrights for 2020 ... Backpatch-through: update all files in master, backpatch legal files through 9.4	6 years ago
Tom Lane	1cff1b95ab	Represent Lists as expansible arrays, not chains of cons-cells. ... Originally, Postgres Lists were a more or less exact reimplementation of Lisp lists, which consist of chains of separately-allocated cons cells, each having a value and a next-cell link. We'd hacked that once before (commit d0b4399d8) to add a separate List header, but the data was still in cons cells. That makes some operations -- notably list_nth() -- O(N), and it's bulky because of the next-cell pointers and per-cell palloc overhead, and it's very cache-unfriendly if the cons cells end up scattered around rather than being adjacent. In this rewrite, we still have List headers, but the data is in a resizable array of values, with no next-cell links. Now we need at most two palloc's per List, and often only one, since we can allocate some values in the same palloc call as the List header. (Of course, extending an existing List may require repalloc's to enlarge the array. But this involves just O(log N) allocations not O(N).) Of course this is not without downsides. The key difficulty is that addition or deletion of a list entry may now cause other entries to move, which it did not before. For example, that breaks foreach() and sister macros, which historically used a pointer to the current cons-cell as loop state. We can repair those macros transparently by making their actual loop state be an integer list index; the exposed "ListCell *" pointer is no longer state carried across loop iterations, but is just a derived value. (In practice, modern compilers can optimize things back to having just one loop state value, at least for simple cases with inline loop bodies.) In principle, this is a semantics change for cases where the loop body inserts or deletes list entries ahead of the current loop index; but I found no such cases in the Postgres code. The change is not at all transparent for code that doesn't use foreach() but chases lists "by hand" using lnext(). The largest share of such code in the backend is in loops that were maintaining "prev" and "next" variables in addition to the current-cell pointer, in order to delete list cells efficiently using list_delete_cell(). However, we no longer need a previous-cell pointer to delete a list cell efficiently. Keeping a next-cell pointer doesn't work, as explained above, but we can improve matters by changing such code to use a regular foreach() loop and then using the new macro foreach_delete_current() to delete the current cell. (This macro knows how to update the associated foreach loop's state so that no cells will be missed in the traversal.) There remains a nontrivial risk of code assuming that a ListCell * pointer will remain good over an operation that could now move the list contents. To help catch such errors, list.c can be compiled with a new define symbol DEBUG_LIST_MEMORY_USAGE that forcibly moves list contents whenever that could possibly happen. This makes list operations significantly more expensive so it's not normally turned on (though it is on by default if USE_VALGRIND is on). There are two notable API differences from the previous code: * lnext() now requires the List's header pointer in addition to the current cell's address. * list_delete_cell() no longer requires a previous-cell argument. These changes are somewhat unfortunate, but on the other hand code using either function needs inspection to see if it is assuming anything it shouldn't, so it's not all bad. Programmers should be aware of these significant performance changes: * list_nth() and related functions are now O(1); so there's no major access-speed difference between a list and an array. * Inserting or deleting a list element now takes time proportional to the distance to the end of the list, due to moving the array elements. (However, it typically *doesn't* require palloc or pfree, so except in long lists it's probably still faster than before.) Notably, lcons() used to be about the same cost as lappend(), but that's no longer true if the list is long. Code that uses lcons() and list_delete_first() to maintain a stack might usefully be rewritten to push and pop at the end of the list rather than the beginning. * There are now list_insert_nth...() and list_delete_nth...() functions that add or remove a list cell identified by index. These have the data-movement penalty explained above, but there's no search penalty. * list_concat() and variants now copy the second list's data into storage belonging to the first list, so there is no longer any sharing of cells between the input lists. The second argument is now declared "const List *" to reflect that it isn't changed. This patch just does the minimum needed to get the new implementation in place and fix bugs exposed by the regression tests. As suggested by the foregoing, there's a fair amount of followup work remaining to do. Also, the ENABLE_LIST_COMPAT macros are finally removed in this commit. Code using those should have been gone a dozen years ago. Patch by me; thanks to David Rowley, Jesper Pedersen, and others for review. Discussion: https://postgr.es/m/11587.1550975080@sss.pgh.pa.us	7 years ago
Michael Paquier	2ab6d28d23	Fix crash with pg_partition_root ... Trying to call the function with the top-most parent of a partition tree was leading to a crash. In this case the correct result is to return the top-most parent itself. Reported-by: Álvaro Herrera Author: Michael Paquier Reviewed-by: Amit Langote Discussion: https://postgr.es/m/20190322032612.GA323@alvherre.pgsql	7 years ago
Alvaro Herrera	b96f6b1948	pg_partition_ancestors ... Adds another introspection feature for partitioning, necessary for further psql patches. Reviewed-by: Michaël Paquier Discussion: https://postgr.es/m/20190226222757.GA31622@alvherre.pgsql	7 years ago
Michael Paquier	3422955735	Consider only relations part of partition trees in partition functions ... This changes the partition functions so as tables and indexes which are not part of partition trees are handled the same way as what is done for undefined objects and unsupported relkinds: pg_partition_tree() returns no rows and pg_partition_root() returns a NULL result. Hence, partitioned tables, partitioned indexes and relations whose flag pg_class.relispartition is set are considered as valid objects to process. Previously, tables and indexes not included in a partition tree were processed the same way as a partition or a partitioned table, which caused the functions to return inconsistent results for inherited tables, especially when inheriting from multiple tables. Reported-by: Álvaro Herrera Author: Amit Langote, Michael Paquier Reviewed-by: Tom Lane Discussion: https://postgr.es/m/20190228193203.GA26151@alvherre.pgsql	7 years ago
Michael Paquier	0f3cdf873e	Make pg_partition_tree return no rows on unsupported and undefined objects ... The function was tweaked so as it returned one row full of NULLs when working on an unsupported relkind or an undefined object as of cc53123, and after discussion with Amit and Álvaro it looks more natural to make it return no rows. Author: Michael Paquier Reviewed-by: Álvaro Herrera, Amit Langote Discussion: https://postgr.es/m/20190227184808.GA17357@alvherre.pgsql	7 years ago
Michael Paquier	3677a0b26b	Add pg_partition_root to display top-most parent of a partition tree ... This is useful when looking at partition trees with multiple layers, and combined with pg_partition_tree, it provides the possibility to show up an entire tree by just knowing one member at any level. Author: Michael Paquier Reviewed-by: Álvaro Herrera, Amit Langote Discussion: https://postgr.es/m/20181207014015.GP2407@paquier.xyz	7 years ago
Bruce Momjian	97c39498e5	Update copyright for 2019 ... Backpatch-through: certain files through 9.4	7 years ago
Michael Paquier	cc53123bcc	Tweak pg_partition_tree for undefined relations and unsupported relkinds ... This fixes a crash which happened when calling the function directly with a relation OID referring to a non-existing object, and changes the behavior so as NULL is returned for unsupported relkinds instead of generating an error. This puts the new function in line with many other system functions, and eases actions like full scans of pg_class. Author: Michael Paquier Reviewed-by: Amit Langote, Stephen Frost Discussion: https://postgr.es/m/20181207010406.GO2407@paquier.xyz	7 years ago
Andres Freund	578b229718	Remove WITH OIDS support, change oid catalog column visibility. ... Previously tables declared WITH OIDS, including a significant fraction of the catalog tables, stored the oid column not as a normal column, but as part of the tuple header. This special column was not shown by default, which was somewhat odd, as it's often (consider e.g. pg_class.oid) one of the more important parts of a row. Neither pg_dump nor COPY included the contents of the oid column by default. The fact that the oid column was not an ordinary column necessitated a significant amount of special case code to support oid columns. That already was painful for the existing, but upcoming work aiming to make table storage pluggable, would have required expanding and duplicating that "specialness" significantly. WITH OIDS has been deprecated since 2005 (commit ff02d0a05280e0). Remove it. Removing includes: - CREATE TABLE and ALTER TABLE syntax for declaring the table to be WITH OIDS has been removed (WITH (oids[ = true]) will error out) - pg_dump does not support dumping tables declared WITH OIDS and will issue a warning when dumping one (and ignore the oid column). - restoring an pg_dump archive with pg_restore will warn when restoring a table with oid contents (and ignore the oid column) - COPY will refuse to load binary dump that includes oids. - pg_upgrade will error out when encountering tables declared WITH OIDS, they have to be altered to remove the oid column first. - Functionality to access the oid of the last inserted row (like plpgsql's RESULT_OID, spi's SPI_lastoid, ...) has been removed. The syntax for declaring a table WITHOUT OIDS (or WITH (oids = false) for CREATE TABLE) is still supported. While that requires a bit of support code, it seems unnecessary to break applications / dumps that do not use oids, and are explicit about not using them. The biggest user of WITH OID columns was postgres' catalog. This commit changes all 'magic' oid columns to be columns that are normally declared and stored. To reduce unnecessary query breakage all the newly added columns are still named 'oid', even if a table's column naming scheme would indicate 'reloid' or such. This obviously requires adapting a lot code, mostly replacing oid access via HeapTupleGetOid() with access to the underlying Form_pg_*->oid column. The bootstrap process now assigns oids for all oid columns in genbki.pl that do not have an explicit value (starting at the largest oid previously used), only oids assigned later by oids will be above FirstBootstrapObjectId. As the oid column now is a normal column the special bootstrap syntax for oids has been removed. Oids are not automatically assigned during insertion anymore, all backend code explicitly assigns oids with GetNewOidWithIndex(). For the rare case that insertions into the catalog via SQL are called for the new pg_nextoid() function can be used (which only works on catalog tables). The fact that oid columns on system tables are now normal columns means that they will be included in the set of columns expanded by * (i.e. SELECT * FROM pg_class will now include the table's oid, previously it did not). It'd not technically be hard to hide oid column by default, but that'd mean confusing behavior would either have to be carried forward forever, or it'd cause breakage down the line. While it's not unlikely that further adjustments are needed, the scope/invasiveness of the patch makes it worthwhile to get merge this now. It's painful to maintain externally, too complicated to commit after the code code freeze, and a dependency of a number of other patches. Catversion bump, for obvious reasons. Author: Andres Freund, with contributions by John Naylor Discussion: https://postgr.es/m/20180930034810.ywp2c7awz7opzcfr@alap3.anarazel.de	7 years ago
Michael Paquier	d5eec4eefd	Add pg_partition_tree to display information about partitions ... This new function is useful to display a full tree of partitions with a partitioned table given in output, and avoids the need of any complex WITH RECURSIVE query when looking at partition trees which are deep multiple levels. It returns a set of records, one for each partition, containing the partition's name, its immediate parent's name, a boolean value telling if the relation is a leaf in the tree and an integer telling its level in the partition tree with given table considered as root, beginning at zero for the root, and incrementing by one each time the scan goes one level down. Author: Amit Langote Reviewed-by: Jesper Pedersen, Michael Paquier, Robert Haas Discussion: https://postgr.es/m/8d00e51a-9a51-ad02-d53e-ba6bf50b2e52@lab.ntt.co.jp	7 years ago