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* Update copyright for 2025Bruce Momjian2025-01-01
| | | | Backpatch-through: 13
* Optimize alignment calculations in tuple form/deformDavid Rowley2024-12-21
| | | | | | | | | | | | | | | | | | | | | Here we convert CompactAttribute.attalign from a char, which is directly derived from pg_attribute.attalign into a uint8, which stores the number of bytes to align the column's value by in the tuple. This allows tuple deformation and tuple size calculations to move away from using the inefficient att_align_nominal() macro, which manually checks each TYPALIGN_* char to translate that into the alignment bytes for the given type. Effectively, this commit changes those to TYPEALIGN calls, which are branchless and only perform some simple arithmetic with some bit-twiddling. The removed branches were often mispredicted by CPUs, especially so in real-world tables which often contain a mishmash of different types with different alignment requirements. Author: David Rowley Reviewed-by: Andres Freund, Victor Yegorov Discussion: https://postgr.es/m/CAApHDvrBztXP3yx=NKNmo3xwFAFhEdyPnvrDg3=M0RhDs+4vYw@mail.gmail.com
* Introduce CompactAttribute array in TupleDesc, take 2David Rowley2024-12-20
| | | | | | | | | | | | | | | | | | | | | | | | The new compact_attrs array stores a few select fields from FormData_pg_attribute in a more compact way, using only 16 bytes per column instead of the 104 bytes that FormData_pg_attribute uses. Using CompactAttribute allows performance-critical operations such as tuple deformation to be performed without looking at the FormData_pg_attribute element in TupleDesc which means fewer cacheline accesses. For some workloads, tuple deformation can be the most CPU intensive part of processing the query. Some testing with 16 columns on a table where the first column is variable length showed around a 10% increase in transactions per second for an OLAP type query performing aggregation on the 16th column. However, in certain cases, the increases were much higher, up to ~25% on one AMD Zen4 machine. This also makes pg_attribute.attcacheoff redundant. A follow-on commit will remove it, thus shrinking the FormData_pg_attribute struct by 4 bytes. Author: David Rowley Reviewed-by: Andres Freund, Victor Yegorov Discussion: https://postgr.es/m/CAApHDvrBztXP3yx=NKNmo3xwFAFhEdyPnvrDg3=M0RhDs+4vYw@mail.gmail.com
* Revert "Introduce CompactAttribute array in TupleDesc"David Rowley2024-12-03
| | | | | | | | | | This reverts commit d28dff3f6cd6a7562fb2c211ac0fb74a33ffd032. Quite a large number of buildfarm members didn't like this commit and it's not yet clear why. Reverting this before too many animals turn red. Discussion: https://postgr.es/m/CAApHDvr9i6T5=iAwQCxFDgMsthr_obVxgwBaEJkC8KUH6yM3Hw@mail.gmail.com
* Introduce CompactAttribute array in TupleDescDavid Rowley2024-12-03
| | | | | | | | | | | | | | | | | | | | | | | | | | The new compact_attrs array stores a few select fields from FormData_pg_attribute in a more compact way, using only 16 bytes per column instead of the 104 bytes that FormData_pg_attribute uses. Using CompactAttribute allows performance-critical operations such as tuple deformation to be performed without looking at the FormData_pg_attribute element in TupleDesc which means fewer cacheline accesses. With this change, NAMEDATALEN could be increased with a much smaller negative impact on performance. For some workloads, tuple deformation can be the most CPU intensive part of processing the query. Some testing with 16 columns on a table where the first column is variable length showed around a 10% increase in transactions per second for an OLAP type query performing aggregation on the 16th column. However, in certain cases, the increases were much higher, up to ~25% on one AMD Zen4 machine. This also makes pg_attribute.attcacheoff redundant. A follow-on commit will remove it, thus shrinking the FormData_pg_attribute struct by 4 bytes. Author: David Rowley Discussion: https://postgr.es/m/CAApHDvrBztXP3yx=NKNmo3xwFAFhEdyPnvrDg3=M0RhDs+4vYw@mail.gmail.com Reviewed-by: Andres Freund, Victor Yegorov
* Update copyright for 2024Bruce Momjian2024-01-03
| | | | | | | | Reported-by: Michael Paquier Discussion: https://postgr.es/m/ZZKTDPxBBMt3C0J9@paquier.xyz Backpatch-through: 12
* Add const to values and nulls argumentsPeter Eisentraut2023-10-10
| | | | | | | This excludes any changes that would change the external AM APIs. Reviewed-by: Aleksander Alekseev <aleksander@timescale.com> Discussion: https://www.postgresql.org/message-id/flat/14c31f4a-0347-0805-dce8-93a9072c05a5%40eisentraut.org
* Update copyright for 2023Bruce Momjian2023-01-02
| | | | Backpatch-through: 11
* Overload index_form_tuple to allow the memory context to be suppliedDavid Rowley2022-07-07
| | | | | | | | | | | | | | | | | | | | | | | 40af10b57 changed things so we make use of a generation memory context for storing tuples to be sorted by tuplesort.c. That change does not play nicely with the changes made in 9f03ca915 (back in 2014). That commit changed things so that index_form_tuple() is called while switched into the tuplestore's tuplecontext. In order to fetch the tuple from the index, index_form_tuple() must do various memory allocations which are unrelated to the storage of the final returned tuple. Although all of these allocations are pfree'd, the fact that we now use a generation context means that the memory for these pfree'd allocations won't be used again by any other allocation due to generation.c's lack of freelists. This could result in sorts used for building indexes exceeding maintenance_work_mem by a very large amount. Here we fix it so we no longer allocate anything apart from the tuple itself into the generation context by adding a new version of index_form_tuple named index_form_tuple_context, which can be called to specify the MemoryContext to allocate the tuple into. Discussion: https://postgr.es/m/CAApHDvrHQkiFRHiGiAS-LMOvJN-eK-s762=tVzBz8ZqUea-a_A@mail.gmail.com Backpatch-through: 15, where 40af10b57 was added.
* Update copyright for 2022Bruce Momjian2022-01-07
| | | | Backpatch-through: 10
* Rethink definition of pg_attribute.attcompression.Tom Lane2021-05-27
| | | | | | | | | | | | | | | | | | | | | | | Redefine '\0' (InvalidCompressionMethod) as meaning "if we need to compress, use the current setting of default_toast_compression". This allows '\0' to be a suitable default choice regardless of datatype, greatly simplifying code paths that initialize tupledescs and the like. It seems like a more user-friendly approach as well, because now the default compression choice doesn't migrate into table definitions, meaning that changing default_toast_compression is usually sufficient to flip an installation's behavior; one needn't tediously issue per-column ALTER SET COMPRESSION commands. Along the way, fix a few minor bugs and documentation issues with the per-column-compression feature. Adopt more robust APIs for SetIndexStorageProperties and GetAttributeCompression. Bump catversion because typical contents of attcompression will now be different. We could get away without doing that, but it seems better to ensure v14 installations all agree on this. (We already forced initdb for beta2, anyway.) Discussion: https://postgr.es/m/626613.1621787110@sss.pgh.pa.us
* Initial pgindent and pgperltidy run for v14.Tom Lane2021-05-12
| | | | | | | | Also "make reformat-dat-files". The only change worthy of note is that pgindent messed up the formatting of launcher.c's struct LogicalRepWorkerId, which led me to notice that that struct wasn't used at all anymore, so I just took it out.
* Support INCLUDE'd columns in SP-GiST.Tom Lane2021-04-05
| | | | | | | | | | | | | Not much to say here: does what it says on the tin. We steal a previously-always-zero bit from the nextOffset field of leaf index tuples in order to track whether there is a nulls bitmap. Otherwise it works about like included columns in other index types. Pavel Borisov, reviewed by Andrey Borodin and Anastasia Lubennikova, and rather heavily editorialized on by me Discussion: https://postgr.es/m/CALT9ZEFi-vMp4faht9f9Junb1nO3NOSjhpxTmbm1UGLMsLqiEQ@mail.gmail.com
* Fix interaction of TOAST compression with expression indexes.Robert Haas2021-03-25
| | | | | | | | | Before, trying to compress a value for insertion into an expression index would crash. Dilip Kumar, with some editing by me. Report by Jaime Casanova. Discussion: http://postgr.es/m/CAJKUy5gcs0zGOp6JXU2mMVdthYhuQpFk=S3V8DOKT=LZC1L36Q@mail.gmail.com
* Allow configurable LZ4 TOAST compression.Robert Haas2021-03-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is now a per-column COMPRESSION option which can be set to pglz (the default, and the only option in up until now) or lz4. Or, if you like, you can set the new default_toast_compression GUC to lz4, and then that will be the default for new table columns for which no value is specified. We don't have lz4 support in the PostgreSQL code, so to use lz4 compression, PostgreSQL must be built --with-lz4. In general, TOAST compression means compression of individual column values, not the whole tuple, and those values can either be compressed inline within the tuple or compressed and then stored externally in the TOAST table, so those properties also apply to this feature. Prior to this commit, a TOAST pointer has two unused bits as part of the va_extsize field, and a compessed datum has two unused bits as part of the va_rawsize field. These bits are unused because the length of a varlena is limited to 1GB; we now use them to indicate the compression type that was used. This means we only have bit space for 2 more built-in compresison types, but we could work around that problem, if necessary, by introducing a new vartag_external value for any further types we end up wanting to add. Hopefully, it won't be too important to offer a wide selection of algorithms here, since each one we add not only takes more coding but also adds a build dependency for every packager. Nevertheless, it seems worth doing at least this much, because LZ4 gets better compression than PGLZ with less CPU usage. It's possible for LZ4-compressed datums to leak into composite type values stored on disk, just as it is for PGLZ. It's also possible for LZ4-compressed attributes to be copied into a different table via SQL commands such as CREATE TABLE AS or INSERT .. SELECT. It would be expensive to force such values to be decompressed, so PostgreSQL has never done so. For the same reasons, we also don't force recompression of already-compressed values even if the target table prefers a different compression method than was used for the source data. These architectural decisions are perhaps arguable but revisiting them is well beyond the scope of what seemed possible to do as part of this project. However, it's relatively cheap to recompress as part of VACUUM FULL or CLUSTER, so this commit adjusts those commands to do so, if the configured compression method of the table happens not to match what was used for some column value stored therein. Dilip Kumar. The original patches on which this work was based were written by Ildus Kurbangaliev, and those were patches were based on even earlier work by Nikita Glukhov, but the design has since changed very substantially, since allow a potentially large number of compression methods that could be added and dropped on a running system proved too problematic given some of the architectural issues mentioned above; the choice of which specific compression method to add first is now different; and a lot of the code has been heavily refactored. More recently, Justin Przyby helped quite a bit with testing and reviewing and this version also includes some code contributions from him. Other design input and review from Tomas Vondra, Álvaro Herrera, Andres Freund, Oleg Bartunov, Alexander Korotkov, and me. Discussion: http://postgr.es/m/20170907194236.4cefce96%40wp.localdomain Discussion: http://postgr.es/m/CAFiTN-uUpX3ck%3DK0mLEk-G_kUQY%3DSNOTeqdaNRR9FMdQrHKebw%40mail.gmail.com
* Update copyright for 2021Bruce Momjian2021-01-02
| | | | Backpatch-through: 9.5
* Introduce macros for typalign and typstorage constants.Tom Lane2020-03-04
| | | | | | | | | | | | | | | | | | | | | Our usual practice for "poor man's enum" catalog columns is to define macros for the possible values and use those, not literal constants, in C code. But for some reason lost in the mists of time, this was never done for typalign/attalign or typstorage/attstorage. It's never too late to make it better though, so let's do that. The reason I got interested in this right now is the need to duplicate some uses of the TYPSTORAGE constants in an upcoming ALTER TYPE patch. But in general, this sort of change aids greppability and readability, so it's a good idea even without any specific motivation. I may have missed a few places that could be converted, and it's even more likely that pending patches will re-introduce some hard-coded references. But that's not fatal --- there's no expectation that we'd actually change any of these values. We can clean up stragglers over time. Discussion: https://postgr.es/m/16457.1583189537@sss.pgh.pa.us
* Update copyrights for 2020Bruce Momjian2020-01-01
| | | | Backpatch-through: update all files in master, backpatch legal files through 9.4
* Rename some toasting functions based on whether they are heap-specific.Robert Haas2019-10-04
| | | | | | | | | | | | | | | | | | | | | | The old names for the attribute-detoasting functions names included the word "heap," which seems outdated now that the heap is only one of potentially many table access methods. On the other hand, toast_insert_or_update and toast_delete are heap-specific, so rename them by adding "heap_" as a prefix. Not all of the work of making the TOAST system fully accessible to AMs other than the heap is done yet, but there seems to be little harm in getting this renaming out of the way now. Commit 8b94dab06617ef80a0901ab103ebd8754427ef5a already divided up the functions among various files partially according to whether it was intended that they should be heap-specific or AM-agnostic, so this is just clarifying the division contemplated by that commit. Patch by me, reviewed and tested by Prabhat Sabu, Thomas Munro, Andres Freund, and Álvaro Herrera. Discussion: http://postgr.es/m/CA+TgmoZv-=2iWM4jcw5ZhJeL18HF96+W1yJeYrnGMYdkFFnEpQ@mail.gmail.com
* Split tuptoaster.c into three separate files.Robert Haas2019-09-05
| | | | | | | | | | | | | | | | | | | | | | | | detoast.c/h contain functions required to detoast a datum, partially or completely, plus a few other utility functions for examining the size of toasted datums. toast_internals.c/h contain functions that are used internally to the TOAST subsystem but which (mostly) do not need to be accessed from outside. heaptoast.c/h contains code that is intrinsically specific to the heap AM, either because it operates on HeapTuples or is based on the layout of a heap page. detoast.c and toast_internals.c are placed in src/backend/access/common rather than src/backend/access/heap. At present, both files still have dependencies on the heap, but that will be improved in a future commit. Patch by me, reviewed and tested by Prabhat Sabu, Thomas Munro, Andres Freund, and Álvaro Herrera. Discussion: http://postgr.es/m/CA+TgmoZv-=2iWM4jcw5ZhJeL18HF96+W1yJeYrnGMYdkFFnEpQ@mail.gmail.com
* Make heap TID a tiebreaker nbtree index column.Peter Geoghegan2019-03-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make nbtree treat all index tuples as having a heap TID attribute. Index searches can distinguish duplicates by heap TID, since heap TID is always guaranteed to be unique. This general approach has numerous benefits for performance, and is prerequisite to teaching VACUUM to perform "retail index tuple deletion". Naively adding a new attribute to every pivot tuple has unacceptable overhead (it bloats internal pages), so suffix truncation of pivot tuples is added. This will usually truncate away the "extra" heap TID attribute from pivot tuples during a leaf page split, and may also truncate away additional user attributes. This can increase fan-out, especially in a multi-column index. Truncation can only occur at the attribute granularity, which isn't particularly effective, but works well enough for now. A future patch may add support for truncating "within" text attributes by generating truncated key values using new opclass infrastructure. Only new indexes (BTREE_VERSION 4 indexes) will have insertions that treat heap TID as a tiebreaker attribute, or will have pivot tuples undergo suffix truncation during a leaf page split (on-disk compatibility with versions 2 and 3 is preserved). Upgrades to version 4 cannot be performed on-the-fly, unlike upgrades from version 2 to version 3. contrib/amcheck continues to work with version 2 and 3 indexes, while also enforcing stricter invariants when verifying version 4 indexes. These stricter invariants are the same invariants described by "3.1.12 Sequencing" from the Lehman and Yao paper. A later patch will enhance the logic used by nbtree to pick a split point. This patch is likely to negatively impact performance without smarter choices around the precise point to split leaf pages at. Making these two mostly-distinct sets of enhancements into distinct commits seems like it might clarify their design, even though neither commit is particularly useful on its own. The maximum allowed size of new tuples is reduced by an amount equal to the space required to store an extra MAXALIGN()'d TID in a new high key during leaf page splits. The user-facing definition of the "1/3 of a page" restriction is already imprecise, and so does not need to be revised. However, there should be a compatibility note in the v12 release notes. Author: Peter Geoghegan Reviewed-By: Heikki Linnakangas, Alexander Korotkov Discussion: https://postgr.es/m/CAH2-WzkVb0Kom=R+88fDFb=JSxZMFvbHVC6Mn9LJ2n=X=kS-Uw@mail.gmail.com
* Improve performance of index-only scans with many index columns.Tom Lane2019-03-03
| | | | | | | | | | | | | | | | | | | | StoreIndexTuple was a loop over index_getattr, which is O(N^2) if the index columns are variable-width, and the performance impact is already quite visible at ten columns. The obvious move is to replace that with a call to index_deform_tuple ... but that's *also* a loop over index_getattr. Improve it to be essentially a clone of heap_deform_tuple. (There are a few other places that loop over all index columns with index_getattr, and perhaps should be changed likewise, but most of them don't seem performance-critical. Anyway, the rest would mostly only be interested in the index key columns, which there aren't likely to be so many of. Wide index tuples are a new thing with INCLUDE.) Konstantin Knizhnik Discussion: https://postgr.es/m/e06b2d27-04fc-5c0e-bb8c-ecd72aa24959@postgrespro.ru
* Don't include heapam.h from others headers.Andres Freund2019-01-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | heapam.h previously was included in a number of widely used headers (e.g. execnodes.h, indirectly in executor.h, ...). That's problematic on its own, as heapam.h contains a lot of low-level details that don't need to be exposed that widely, but becomes more problematic with the upcoming introduction of pluggable table storage - it seems inappropriate for heapam.h to be included that widely afterwards. heapam.h was largely only included in other headers to get the HeapScanDesc typedef (which was defined in heapam.h, even though HeapScanDescData is defined in relscan.h). The better solution here seems to be to just use the underlying struct (forward declared where necessary). Similar for BulkInsertState. Another problem was that LockTupleMode was used in executor.h - parts of the file tried to cope without heapam.h, but due to the fact that it indirectly included it, several subsequent violations of that goal were not not noticed. We could just reuse the approach of declaring parameters as int, but it seems nicer to move LockTupleMode to lockoptions.h - that's not a perfect location, but also doesn't seem bad. As a number of files relied on implicitly included heapam.h, a significant number of files grew an explicit include. It's quite probably that a few external projects will need to do the same. Author: Andres Freund Reviewed-By: Alvaro Herrera Discussion: https://postgr.es/m/20190114000701.y4ttcb74jpskkcfb@alap3.anarazel.de
* Update copyright for 2019Bruce Momjian2019-01-02
| | | | Backpatch-through: certain files through 9.4
* Post-feature-freeze pgindent run.Tom Lane2018-04-26
| | | | Discussion: https://postgr.es/m/15719.1523984266@sss.pgh.pa.us
* Adjust INCLUDE index truncation comments and code.Teodor Sigaev2018-04-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add several assertions that ensure that we're dealing with a pivot tuple without non-key attributes where that's expected. Also, remove the assertion within _bt_isequal(), restoring the v10 function signature. A similar check will be performed for the page highkey within _bt_moveright() in most cases. Also avoid dropping all objects within regression tests, to increase pg_dump test coverage for INCLUDE indexes. Rather than using infrastructure that's generally intended to be used with reference counted heap tuple descriptors during truncation, use the same function that was introduced to store flat TupleDescs in shared memory (we use a temp palloc'd buffer). This isn't strictly necessary, but seems more future-proof than the old approach. It also lets us avoid including rel.h within indextuple.c, which was arguably a modularity violation. Also, we now call index_deform_tuple() with the truncated TupleDesc, not the source TupleDesc, since that's more robust, and saves a few cycles. In passing, fix a memory leak by pfree'ing truncated pivot tuple memory during CREATE INDEX. Also pfree during a page split, just to be consistent. Refactor _bt_check_natts() to be more readable. Author: Peter Geoghegan with some editorization by me Reviewed by: Alexander Korotkov, Teodor Sigaev Discussion: https://www.postgresql.org/message-id/CAH2-Wz%3DkCWuXeMrBCopC-tFs3FbiVxQNjjgNKdG2sHxZ5k2y3w%40mail.gmail.com
* Remove unused variable in non-assert-enabled buildTeodor Sigaev2018-04-08
| | | | | | Use field of structure in Assert directly Jeff Janes
* Indexes with INCLUDE columns and their support in B-treeTeodor Sigaev2018-04-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduces INCLUDE clause to index definition. This clause specifies a list of columns which will be included as a non-key part in the index. The INCLUDE columns exist solely to allow more queries to benefit from index-only scans. Also, such columns don't need to have appropriate operator classes. Expressions are not supported as INCLUDE columns since they cannot be used in index-only scans. Index access methods supporting INCLUDE are indicated by amcaninclude flag in IndexAmRoutine. For now, only B-tree indexes support INCLUDE clause. In B-tree indexes INCLUDE columns are truncated from pivot index tuples (tuples located in non-leaf pages and high keys). Therefore, B-tree indexes now might have variable number of attributes. This patch also provides generic facility to support that: pivot tuples contain number of their attributes in t_tid.ip_posid. Free 13th bit of t_info is used for indicating that. This facility will simplify further support of index suffix truncation. The changes of above are backward-compatible, pg_upgrade doesn't need special handling of B-tree indexes for that. Bump catalog version Author: Anastasia Lubennikova with contribition by Alexander Korotkov and me Reviewed by: Peter Geoghegan, Tomas Vondra, Antonin Houska, Jeff Janes, David Rowley, Alexander Korotkov Discussion: https://www.postgresql.org/message-id/flat/56168952.4010101@postgrespro.ru
* Update copyright for 2018Bruce Momjian2018-01-02
| | | | Backpatch-through: certain files through 9.3
* Change tupledesc->attrs[n] to TupleDescAttr(tupledesc, n).Andres Freund2017-08-20
| | | | | | | | | | | This is a mechanical change in preparation for a later commit that will change the layout of TupleDesc. Introducing a macro to abstract the details of where attributes are stored will allow us to change that in separate step and revise it in future. Author: Thomas Munro, editorialized by Andres Freund Reviewed-By: Andres Freund Discussion: https://postgr.es/m/CAEepm=0ZtQ-SpsgCyzzYpsXS6e=kZWqk3g5Ygn3MDV7A8dabUA@mail.gmail.com
* Phase 3 of pgindent updates.Tom Lane2017-06-21
| | | | | | | | | | | | | | | | | | | | | | | | | Don't move parenthesized lines to the left, even if that means they flow past the right margin. By default, BSD indent lines up statement continuation lines that are within parentheses so that they start just to the right of the preceding left parenthesis. However, traditionally, if that resulted in the continuation line extending to the right of the desired right margin, then indent would push it left just far enough to not overrun the margin, if it could do so without making the continuation line start to the left of the current statement indent. That makes for a weird mix of indentations unless one has been completely rigid about never violating the 80-column limit. This behavior has been pretty universally panned by Postgres developers. Hence, disable it with indent's new -lpl switch, so that parenthesized lines are always lined up with the preceding left paren. This patch is much less interesting than the first round of indent changes, but also bulkier, so I thought it best to separate the effects. Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
* Update copyright via script for 2017Bruce Momjian2017-01-03
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* Revert CREATE INDEX ... INCLUDING ...Teodor Sigaev2016-04-08
| | | | | | It's not ready yet, revert two commits 690c543550b0d2852060c18d270cdb534d339d9a - unstable test output 386e3d7609c49505e079c40c65919d99feb82505 - patch itself
* CREATE INDEX ... INCLUDING (column[, ...])Teodor Sigaev2016-04-08
| | | | | | | | | | Now indexes (but only B-tree for now) can contain "extra" column(s) which doesn't participate in index structure, they are just stored in leaf tuples. It allows to use index only scan by using single index instead of two or more indexes. Author: Anastasia Lubennikova with minor editorializing by me Reviewers: David Rowley, Peter Geoghegan, Jeff Janes
* Update copyright for 2016Bruce Momjian2016-01-02
| | | | Backpatch certain files through 9.1
* Update copyright for 2015Bruce Momjian2015-01-06
| | | | Backpatch certain files through 9.0
* Avoid copying index tuples when building an index.Robert Haas2014-07-01
| | | | | | | | | | | | The previous code, perhaps out of concern for avoid memory leaks, formed the tuple in one memory context and then copied it to another memory context. However, this doesn't appear to be necessary, since index_form_tuple and the functions it calls take precautions against leaking memory. In my testing, building the tuple directly inside the sort context shaves several percent off the index build time. Rearrange things so we do that. Patch by me. Review by Amit Kapila, Tom Lane, Andres Freund.
* pgindent run for 9.4Bruce Momjian2014-05-06
| | | | | This includes removing tabs after periods in C comments, which was applied to back branches, so this change should not effect backpatching.
* Fix failure to detoast fields in composite elements of structured types.Tom Lane2014-05-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we have an array of records stored on disk, the individual record fields cannot contain out-of-line TOAST pointers: the tuptoaster.c mechanisms are only prepared to deal with TOAST pointers appearing in top-level fields of a stored row. The same applies for ranges over composite types, nested composites, etc. However, the existing code only took care of expanding sub-field TOAST pointers for the case of nested composites, not for other structured types containing composites. For example, given a command such as UPDATE tab SET arraycol = ARRAY[(ROW(x,42)::mycompositetype] ... where x is a direct reference to a field of an on-disk tuple, if that field is long enough to be toasted out-of-line then the TOAST pointer would be inserted as-is into the array column. If the source record for x is later deleted, the array field value would become a dangling pointer, leading to errors along the line of "missing chunk number 0 for toast value ..." when the value is referenced. A reproducible test case for this was provided by Jan Pecek, but it seems likely that some of the "missing chunk number" reports we've heard in the past were caused by similar issues. Code-wise, the problem is that PG_DETOAST_DATUM() is not adequate to produce a self-contained Datum value if the Datum is of composite type. Seen in this light, the problem is not just confined to arrays and ranges, but could also affect some other places where detoasting is done in that way, for example form_index_tuple(). I tried teaching the array code to apply toast_flatten_tuple_attribute() along with PG_DETOAST_DATUM() when the array element type is composite, but this was messy and imposed extra cache lookup costs whether or not any TOAST pointers were present, indeed sometimes when the array element type isn't even composite (since sometimes it takes a typcache lookup to find that out). The idea of extending that approach to all the places that currently use PG_DETOAST_DATUM() wasn't attractive at all. This patch instead solves the problem by decreeing that composite Datum values must not contain any out-of-line TOAST pointers in the first place; that is, we expand out-of-line fields at the point of constructing a composite Datum, not at the point where we're about to insert it into a larger tuple. This rule is applied only to true composite Datums, not to tuples that are being passed around the system as tuples, so it's not as invasive as it might sound at first. With this approach, the amount of code that has to be touched for a full solution is greatly reduced, and added cache lookup costs are avoided except when there actually is a TOAST pointer that needs to be inlined. The main drawback of this approach is that we might sometimes dereference a TOAST pointer that will never actually be used by the query, imposing a rather large cost that wasn't there before. On the other side of the coin, if the field value is used multiple times then we'll come out ahead by avoiding repeat detoastings. Experimentation suggests that common SQL coding patterns are unaffected either way, though. Applications that are very negatively affected could be advised to modify their code to not fetch columns they won't be using. In future, we might consider reverting this solution in favor of detoasting only at the point where data is about to be stored to disk, using some method that can drill down into multiple levels of nested structured types. That will require defining new APIs for structured types, though, so it doesn't seem feasible as a back-patchable fix. Note that this patch changes HeapTupleGetDatum() from a macro to a function call; this means that any third-party code using that macro will not get protection against creating TOAST-pointer-containing Datums until it's recompiled. The same applies to any uses of PG_RETURN_HEAPTUPLEHEADER(). It seems likely that this is not a big problem in practice: most of the tuple-returning functions in core and contrib produce outputs that could not possibly be toasted anyway, and the same probably holds for third-party extensions. This bug has existed since TOAST was invented, so back-patch to all supported branches.
* Allow use of "z" flag in our printf calls, and use it where appropriate.Tom Lane2014-01-23
| | | | | | | | | | | | | | | | | | | | | | | | | Since C99, it's been standard for printf and friends to accept a "z" size modifier, meaning "whatever size size_t has". Up to now we've generally dealt with printing size_t values by explicitly casting them to unsigned long and using the "l" modifier; but this is really the wrong thing on platforms where pointers are wider than longs (such as Win64). So let's start using "z" instead. To ensure we can do that on all platforms, teach src/port/snprintf.c to understand "z", and add a configure test to force use of that implementation when the platform's version doesn't handle "z". Having done that, modify a bunch of places that were using the unsigned-long hack to use "z" instead. This patch doesn't pretend to have gotten everyplace that could benefit, but it catches many of them. I made an effort in particular to ensure that all uses of the same error message text were updated together, so as not to increase the number of translatable strings. It's possible that this change will result in format-string warnings from pre-C99 compilers. We might have to reconsider if there are any popular compilers that will warn about this; but let's start by seeing what the buildfarm thinks. Andres Freund, with a little additional work by me
* Update copyright for 2014Bruce Momjian2014-01-07
| | | | | Update all files in head, and files COPYRIGHT and legal.sgml in all back branches.
* Update copyrights for 2013Bruce Momjian2013-01-01
| | | | | Fully update git head, and update back branches in ./COPYRIGHT and legal.sgml files.
* Update copyright notices for year 2012.Bruce Momjian2012-01-01
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* pgindent run before PG 9.1 beta 1.Bruce Momjian2011-04-10
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* Stamp copyrights for year 2011.Bruce Momjian2011-01-01
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* Remove cvs keywords from all files.Magnus Hagander2010-09-20
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* Remove partial, broken support for NULL pointers when fetching attributes.Robert Haas2010-01-10
| | | | | | | | | | | | | | Previously, fastgetattr() and heap_getattr() tested their fourth argument against a null pointer, but any attempt to use them with a literal-NULL fourth argument evaluated to *(void *)0, resulting in a compiler error. Remove these NULL tests to avoid leading future readers of this code to believe that this has a chance of working. Also clean up related legacy code in nocachegetattr(), heap_getsysattr(), and nocache_index_getattr(). The new coding standard is that any code which calls a getattr-type function or macro which takes an isnull argument MUST pass a valid boolean pointer. Per discussion with Bruce Momjian, Tom Lane, Alvaro Herrera.
* Update copyright for the year 2010.Bruce Momjian2010-01-02
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* Improve unique-constraint-violation error messages to include the exactTom Lane2009-08-01
| | | | | | | | | values being complained of. In passing, also remove the arbitrary length limitation in the similar error detail message for foreign key violations. Itagaki Takahiro
* 8.4 pgindent run, with new combined Linux/FreeBSD/MinGW typedef listBruce Momjian2009-06-11
| | | | provided by Andrew.
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