summaryrefslogtreecommitdiff
path: root/src/backend/access/common
AgeCommit message (Collapse)Author
2019-02-06Fix heap_getattr() handling of fast defaults.Andres Freund
Previously heap_getattr() returned NULL for attributes with a fast default value (c.f. 16828d5c0273), as it had no handling whatsoever for that case. A previous fix, 7636e5c60f, attempted to fix issues caused by this oversight, but just expanding OLD tuples for triggers doesn't actually solve the underlying issue. One known consequence of this bug is that the check for HOT updates can return the wrong result, when a previously fast-default'ed column is set to NULL. Which in turn means that an index over a column with fast default'ed columns might be corrupt if the underlying column(s) allow NULLs. Fix by handling fast default columns in heap_getattr(), remove now superfluous expansion in GetTupleForTrigger(). Author: Andres Freund Discussion: https://postgr.es/m/20190201162404.onngi77f26baem4g@alap3.anarazel.de Backpatch: 11, where fast defaults were introduced
2019-01-26Simplify restriction handling of two-phase commit for temporary objectsMichael Paquier
There were two flags used to track the access to temporary tables and to the temporary namespace of a session which are used to restrict PREPARE TRANSACTION, however the first control flag is a concept included in the second. This removes the flag for temporary table tracking, keeping around only the one at namespace level. Author: Michael Paquier Reviewed-by: Álvaro Herrera Discussion: https://postgr.es/m/20190118053126.GH1883@paquier.xyz
2019-01-21Introduce access/{table.h, relation.h}, for generic functions from heapam.h.Andres Freund
access/heapam contains functions that are very storage specific (say heap_insert() and a lot of lower level functions), and fairly generic infrastructure like relation_open(), heap_open() etc. In the upcoming pluggable storage work we're introducing a layer between table accesses in general and heapam, to allow for different storage methods. For a bit cleaner separation it thus seems advantageous to move generic functions like the aforementioned to their own headers. access/relation.h will contain relation_open() etc, and access/table.h will contain table_open() (formerly known as heap_open()). I've decided for table.h not to include relation.h, but we might change that at a later stage. relation.h already exists in another directory, but the other plausible name (rel.h) also conflicts. It'd be nice if there were a non-conflicting name, but nobody came up with a suggestion. It's possible that the appropriate way to address the naming conflict would be to rename nodes/relation.h, which isn't particularly well named. To avoid breaking a lot of extensions that just use heap_open() etc, table.h has macros mapping the old names to the new ones, and heapam.h includes relation, table.h. That also allows to keep the bulk renaming of existing callers in a separate commit. Author: Andres Freund Discussion: https://postgr.es/m/20190111000539.xbv7s6w7ilcvm7dp@alap3.anarazel.de
2019-01-15Finish reverting "recheck_on_update" patch.Tom Lane
This reverts commit c203d6cf8 and some follow-on fixes, completing the task begun in commit 5d28c9bd7. If that feature is ever resurrected, the code will look quite a bit different from this, so it seems best to start from a clean slate. The v11 branch is not touched; in that branch, the recheck_on_update storage option remains present, but nonfunctional and undocumented. Discussion: https://postgr.es/m/20190114223409.3tcvejfhlvbucrv5@alap3.anarazel.de
2019-01-14Make naming of tupdesc related structs more consistent with the rest of PG.Andres Freund
We usually don't change the name of structs between the struct name itself and the name of the typedef. Additionally, structs that are usually used via a typedef that hides being a pointer, are commonly suffixed Data. Change tupdesc code to follow those convention. This is triggered by a future patch that intends to forward declare TupleDescData in another header - keeping with the naming scheme makes that easier to understand. Author: Andres Freund Discussion: https://postgr.es/m/20190114000701.y4ttcb74jpskkcfb@alap3.anarazel.de
2019-01-14Don't include heapam.h from others headers.Andres Freund
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
2019-01-02Update copyright for 2019Bruce Momjian
Backpatch-through: certain files through 9.4
2018-12-18Make collation-aware system catalog columns use "C" collation.Tom Lane
Up to now we allowed text columns in system catalogs to use collation "default", but that isn't really safe because it might mean something different in template0 than it means in a database cloned from template0. In particular, this could mean that cloned pg_statistic entries for such columns weren't entirely valid, possibly leading to bogus planner estimates, though (probably) not any outright failures. In the wake of commit 5e0928005, a better solution is available: if we label such columns with "C" collation, then their pg_statistic entries will also use that collation and hence will be valid independently of the database collation. This also provides a cleaner solution for indexes on such columns than the hack added by commit 0b28ea79c: the indexes will naturally inherit "C" collation and don't have to be forced to use text_pattern_ops. Also, with the planned improvement of type "name" to be collation-aware, this policy will apply cleanly to both text and name columns. Because of the pg_statistic angle, we should also apply this policy to the tables in information_schema. This patch does that by adjusting information_schema's textual domain types to specify "C" collation. That has the user-visible effect that order-sensitive comparisons to textual information_schema view columns will now use "C" collation by default. The SQL standard says that the collation of those view columns is implementation-defined, so I think this is legal per spec. At some point this might allow for translation of such comparisons into indexable conditions on the underlying "name" columns, although additional work will be needed before that can happen. Discussion: https://postgr.es/m/19346.1544895309@sss.pgh.pa.us
2018-12-10Make TupleDescInitBuiltinEntry throw error for unsupported types.Tom Lane
Previously, it would just pass back a partially-uninitialized tupdesc, which doesn't seem like a safe or useful behavior. Backpatch to v10 where this code came in. Discussion: https://postgr.es/m/30830.1544384975@sss.pgh.pa.us
2018-11-20Remove WITH OIDS support, change oid catalog column visibility.Andres Freund
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
2018-11-16Make TupleTableSlots extensible, finish split of existing slot type.Andres Freund
This commit completes the work prepared in 1a0586de36, splitting the old TupleTableSlot implementation (which could store buffer, heap, minimal and virtual slots) into four different slot types. As described in the aforementioned commit, this is done with the goal of making tuple table slots extensible, to allow for pluggable table access methods. To achieve runtime extensibility for TupleTableSlots, operations on slots that can differ between types of slots are performed using the TupleTableSlotOps struct provided at slot creation time. That includes information from the size of TupleTableSlot struct to be allocated, initialization, deforming etc. See the struct's definition for more detailed information about callbacks TupleTableSlotOps. I decided to rename TTSOpsBufferTuple to TTSOpsBufferHeapTuple and ExecCopySlotTuple to ExecCopySlotHeapTuple, as that seems more consistent with other naming introduced in recent patches. There's plenty optimization potential in the slot implementation, but according to benchmarking the state after this commit has similar performance characteristics to before this set of changes, which seems sufficient. There's a few changes in execReplication.c that currently need to poke through the slot abstraction, that'll be repaired once the pluggable storage patchset provides the necessary infrastructure. Author: Andres Freund and Ashutosh Bapat, with changes by Amit Khandekar Discussion: https://postgr.es/m/20181105210039.hh4vvi4vwoq5ba2q@alap3.anarazel.de
2018-10-24Correctly set t_self for heap tuples in expand_tupleAndrew Dunstan
Commit 16828d5c0 incorrectly set an invalid pointer for t_self for heap tuples. This patch correctly copies it from the source tuple, and includes a regression test that relies on it being set correctly. Backpatch to release 11. Fixes bug #15448 reported by Tillmann Schulz Diagnosis and test case by Amit Langote
2018-10-15Move TupleTableSlots boolean member into one flag variable.Andres Freund
There's several reasons for this change: 1) It reduces the total size of TupleTableSlot / reduces alignment padding, making the commonly accessed members fit into a single cacheline (but we currently do not force proper alignment, so that's not yet guaranteed to be helpful) 2) Combining the booleans into a flag allows to combine read/writes from memory. 3) With the upcoming slot abstraction changes, it allows to have core and extended flags, in a memory efficient way. Author: Ashutosh Bapat and Andres Freund Discussion: https://postgr.es/m/20180220224318.gw4oe5jadhpmcdnm@alap3.anarazel.de
2018-10-15Move generic slot support functions from heaptuple.c into execTuples.c.Andres Freund
heaptuple.c was never a particular good fit for slot_getattr(), slot_getsomeattrs() and slot_getmissingattrs(), but in upcoming changes slots will be made more abstract (allowing slots that contain different types of tuples), making it clearly the wrong place. Note that slot_deform_tuple() remains in it's current place, as it clearly deals with a HeapTuple. getmissingattrs() also remains, but it's less clear that that's correct - but execTuples.c wouldn't be the right place. Author: Ashutosh Bapat. Discussion: https://postgr.es/m/20180220224318.gw4oe5jadhpmcdnm@alap3.anarazel.de
2018-10-02Use slots more widely in tuple mapping code and make naming more consistent.Andres Freund
It's inefficient to use a single slot for mapping between tuple descriptors for multiple tuples, as previously done when using ConvertPartitionTupleSlot(), as that means the slot's tuple descriptors change for every tuple. Previously we also, via ConvertPartitionTupleSlot(), built new tuples after the mapping even in cases where we, immediately afterwards, access individual columns again. Refactor the code so one slot, on demand, is used for each partition. That avoids having to change the descriptor (and allows to use the more efficient "fixed" tuple slots). Then use slot->slot mapping, to avoid unnecessarily forming a tuple. As the naming between the tuple and slot mapping functions wasn't consistent, rename them to execute_attr_map_{tuple,slot}. It's likely that we'll also rename convert_tuples_by_* to denote that these functions "only" build a map, but that's left for later. Author: Amit Khandekar and Amit Langote, editorialized by me Reviewed-By: Amit Langote, Amit Khandekar, Andres Freund Discussion: https://postgr.es/m/CAJ3gD9fR0wRNeAE8VqffNTyONS_UfFPRpqxhnD9Q42vZB+Jvpg@mail.gmail.com https://postgr.es/m/e4f9d743-cd4b-efb0-7574-da21d86a7f36%40lab.ntt.co.jp Backpatch: -
2018-09-24Fast default trigger and expand_tuple fixesAndrew Dunstan
Ensure that triggers get properly filled in tuples for the OLD value. Also fix the logic of detecting missing null values. The previous logic failed to detect a missing null column before the first missing column with a default. Fixing this has simplified the logic a bit. Regression tests are added to test changes. This should ensure better coverage of expand_tuple(). Original bug reports, and some code and test scripts from Tomas Vondra Backpatch to release 11.
2018-08-23Deduplicate code between slot_getallattrs() and slot_getsomeattrs().Andres Freund
Code in slot_getallattrs() is the same as if slot_getsomeattrs() is called with number of attributes specified in the tuple descriptor. Implement it that way instead of duplicating the code between those two functions. This is part of a patchseries abstracting TupleTableSlots so they can store arbitrary forms of tuples, but is a nice enough cleanup on its own. Author: Ashutosh Bapat Reviewed-By: Andres Freund Discussion: https://postgr.es/m/20180220224318.gw4oe5jadhpmcdnm@alap3.anarazel.de
2018-07-13Improve performance of tuple conversion map generationHeikki Linnakangas
Previously convert_tuples_by_name_map naively performed a search of each outdesc column starting at the first column in indesc and searched each indesc column until a match was found. When partitioned tables had many columns this could result in slow generation of the tuple conversion maps. For INSERT and UPDATE statements that touched few rows, this could mean a very large overhead indeed. We can do a bit better with this loop. It's quite likely that the columns in partitioned tables and their partitions are in the same order, so it makes sense to start searching for each column outer column at the inner column position 1 after where the previous match was found (per idea from Alexander Kuzmenkov). This makes the best case search O(N) instead of O(N^2). The worst case is still O(N^2), but it seems unlikely that would happen. Likewise, in the planner, make_inh_translation_list's search for the matching column could often end up falling back on an O(N^2) type search. This commit also improves that by first checking the column that follows the previous match, instead of the column with the same attnum. If we fail to match here we fallback on the syscache's hashtable lookup. Author: David Rowley Reviewed-by: Alexander Kuzmenkov Discussion: https://www.postgresql.org/message-id/CAKJS1f9-wijVgMdRp6_qDMEQDJJ%2BA_n%3DxzZuTmLx5Fz6cwf%2B8A%40mail.gmail.com
2018-07-11Fix more wrong paths in header commentsAlexander Korotkov
It appears that there are more files, whose header comment paths are wrong. So, fix those paths. No backpatching per proposal of Tom Lane. Discussion: https://postgr.es/m/CAPpHfdsJyYbOj59MOQL%2B4XxdcomLSLfLqBtAvwR%2BpsCqj3ELdQ%40mail.gmail.com
2018-06-27Cosmetic improvements for faster column addition.Amit Kapila
Changed the name of few structure members for the sake of clarity and removed spurious whitespace. Reported-by: Amit Kapila Author: Amit Kapila, based on suggestion by Andrew Dunstan Reviewed-by: Alvaro Herrera Discussion: https://postgr.es/m/CAA4eK1K2znsFpC+NQ9A4vxT4uDxADN4RmvHX0L6Y=aHVo9gB4Q@mail.gmail.com
2018-06-26Fix upper limit for vacuum_cleanup_index_scale_factorAlexander Korotkov
6ca33a88 sets upper limit for vacuum_cleanup_index_scale_factor to DBL_MAX. DBL_MAX appears to be platform-dependent. That causes many buildfarm animals to fail, because we check boundaries of vacuum_cleanup_index_scale_factor in regression tests. This commit changes upper limit from DBL_MAX to just "large enough" limit, which was arbitrary selected as 1e10. Author: Alexander Korotkov Reported-by: Tom Lane, Darafei Praliaskouski Discussion: https://postgr.es/m/CAPpHfdvewmr4PcpRjrkstoNn1n2_6dL-iHRB21CCfZ0efZdBTg%40mail.gmail.com Discussion: https://postgr.es/m/CAC8Q8tLYFOpKNaPS_E7V8KtPdE%3D_TnAn16t%3DA3LuL%3DXjfOO-BQ%40mail.gmail.com
2018-06-26Increase upper limit for vacuum_cleanup_index_scale_factorAlexander Korotkov
Upper limits for vacuum_cleanup_index_scale_factor GUC and reloption were initially set to 100.0 in 857f9c36. However, after further discussion, it appears that some users like to disable B-tree cleanup index scan completely (assuming there are no deleted pages). vacuum_cleanup_index_scale_factor is used barely to protect against stalled index statistics. And after detailed consideration it appears that risk of stalled index statistics is low. And it would be nice to allow advanced users setting higher values of vacuum_cleanup_index_scale_factor. So, set upper limit for these GUC and reloption to DBL_MAX. Author: Alexander Korotkov Reviewed-by: Masahiko Sawada Discussion: https://postgr.es/m/CAC8Q8tJCb%3DgxhzcV7T6ctx7PY-Ux1oA-AsTJc6cAVNsQiYcCzA%40mail.gmail.com
2018-04-26Post-feature-freeze pgindent run.Tom Lane
Discussion: https://postgr.es/m/15719.1523984266@sss.pgh.pa.us
2018-04-19Adjust INCLUDE index truncation comments and code.Teodor Sigaev
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
2018-04-13Prevent segfault in expand_tuple with no missing valuesAndrew Dunstan
Commit 16828d5c forgot to check that it had a set of missing values before trying to retrieve a value from it. An additional query to add coverage for this code is added to the regression test. Per bug report from Andreas Seltenreich.
2018-04-08Remove unused variable in non-assert-enabled buildTeodor Sigaev
Use field of structure in Assert directly Jeff Janes
2018-04-07Indexes with INCLUDE columns and their support in B-treeTeodor Sigaev
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
2018-04-04Skip full index scan during cleanup of B-tree indexes when possibleTeodor Sigaev
Vacuum of index consists from two stages: multiple (zero of more) ambulkdelete calls and one amvacuumcleanup call. When workload on particular table is append-only, then autovacuum isn't intended to touch this table. However, user may run vacuum manually in order to fill visibility map and get benefits of index-only scans. Then ambulkdelete wouldn't be called for indexes of such table (because no heap tuples were deleted), only amvacuumcleanup would be called In this case, amvacuumcleanup would perform full index scan for two objectives: put recyclable pages into free space map and update index statistics. This patch allows btvacuumclanup to skip full index scan when two conditions are satisfied: no pages are going to be put into free space map and index statistics isn't stalled. In order to check first condition, we store oldest btpo_xact in the meta-page. When it's precedes RecentGlobalXmin, then there are some recyclable pages. In order to check second condition we store number of heap tuples observed during previous full index scan by cleanup. If fraction of newly inserted tuples is less than vacuum_cleanup_index_scale_factor, then statistics isn't considered to be stalled. vacuum_cleanup_index_scale_factor can be defined as both reloption and GUC (default). This patch bumps B-tree meta-page version. Upgrade of meta-page is performed "on the fly": during VACUUM meta-page is rewritten with new version. No special handling in pg_upgrade is required. Author: Masahiko Sawada, Alexander Korotkov Review by: Peter Geoghegan, Kyotaro Horiguchi, Alexander Korotkov, Yura Sokolov Discussion: https://www.postgresql.org/message-id/flat/CAD21AoAX+d2oD_nrd9O2YkpzHaFr=uQeGr9s1rKC3O4ENc568g@mail.gmail.com
2018-04-01Fix a boatload of typos in C comments.Tom Lane
Justin Pryzby Discussion: https://postgr.es/m/20180331105640.GK28454@telsasoft.com
2018-04-01Small cleanups in fast default code.Andrew Dunstan
Problems identified by Andres Freund and Haribabu Kommi
2018-03-27Quick adaption of JIT tuple deforming to the fast default patch.Andres Freund
Instead using memset to set tts_isnull, call the new slot_getmissingattrs(). Also fix a bug (= instead of >=) in the code generation. Normally = is correct, but when repeatedly deforming fields not in a tuple (e.g. deform up to natts + 1 and then natts + 2) >= is needed. Discussion: https://postgr.es/m/20180328010053.i2qvsuuusst4lgmc@alap3.anarazel.de
2018-03-28Fast ALTER TABLE ADD COLUMN with a non-NULL defaultAndrew Dunstan
Currently adding a column to a table with a non-NULL default results in a rewrite of the table. For large tables this can be both expensive and disruptive. This patch removes the need for the rewrite as long as the default value is not volatile. The default expression is evaluated at the time of the ALTER TABLE and the result stored in a new column (attmissingval) in pg_attribute, and a new column (atthasmissing) is set to true. Any existing row when fetched will be supplied with the attmissingval. New rows will have the supplied value or the default and so will never need the attmissingval. Any time the table is rewritten all the atthasmissing and attmissingval settings for the attributes are cleared, as they are no longer needed. The most visible code change from this is in heap_attisnull, which acquires a third TupleDesc argument, allowing it to detect a missing value if there is one. In many cases where it is known that there will not be any (e.g. catalog relations) NULL can be passed for this argument. Andrew Dunstan, heavily modified from an original patch from Serge Rielau. Reviewed by Tom Lane, Andres Freund, Tomas Vondra and David Rowley. Discussion: https://postgr.es/m/31e2e921-7002-4c27-59f5-51f08404c858@2ndQuadrant.com
2018-03-27Allow HOT updates for some expression indexesSimon Riggs
If the value of an index expression is unchanged after UPDATE, allow HOT updates where previously we disallowed them, giving a significant performance boost in those cases. Particularly useful for indexes such as JSON->>field where the JSON value changes but the indexed value does not. Submitted as "surjective indexes" patch, now enabled by use of new "recheck_on_update" parameter. Author: Konstantin Knizhnik Reviewer: Simon Riggs, with much wordsmithing and some cleanup
2018-03-26JIT tuple deforming in LLVM JIT provider.Andres Freund
Performing JIT compilation for deforming gains performance benefits over unJITed deforming from compile-time knowledge of the tuple descriptor. Fixed column widths, NOT NULLness, etc can be taken advantage of. Right now the JITed deforming is only used when deforming tuples as part of expression evaluation (and obviously only if the descriptor is known). It's likely to be beneficial in other cases, too. By default tuple deforming is JITed whenever an expression is JIT compiled. There's a separate boolean GUC controlling it, but that's expected to be primarily useful for development and benchmarking. Docs will follow in a later commit containing docs for the whole JIT feature. Author: Andres Freund Discussion: https://postgr.es/m/20170901064131.tazjxwus3k2w3ybh@alap3.anarazel.de
2018-03-17Fix WHERE CURRENT OF when the referenced cursor uses an index-only scan.Tom Lane
"UPDATE/DELETE WHERE CURRENT OF cursor_name" failed, with an error message like "cannot extract system attribute from virtual tuple", if the cursor was using a index-only scan for the target table. Fix it by digging the current TID out of the indexscan state. It seems likely that the same failure could occur for CustomScan plans and perhaps some FDW plan types, so that leaving this to be treated as an internal error with an obscure message isn't as good an idea as it first seemed. Hence, add a bit of heaptuple.c infrastructure to let us deliver a more on-topic message. I chose to make the message match what you get for the case where execCurrentOf can't identify the target scan node at all, "cursor "foo" is not a simply updatable scan of table "bar"". Perhaps it should be different, but we can always adjust that later. In the future, it might be nice to provide hooks that would let custom scan providers and/or FDWs deal with this in other ways; but that's not a suitable topic for a back-patchable bug fix. It's been like this all along, so back-patch to all supported branches. Yugo Nagata and Tom Lane Discussion: https://postgr.es/m/20180201013349.937dfc5f.nagata@sraoss.co.jp
2018-02-20Use platform independent type for TupleTableSlot->tts_off.Andres Freund
Previously tts_off was, for unknown reasons, of type long. For one that's unnecessary as tuples are restricted in length, for another long would be a bad choice of type even if that weren't the case, as it's not reliably wider than an int. Also HeapTupleHeader->t_len is a uint32. This is split off from a larger patch implementing JITed tuple deforming. Seems like an independent improvement, as tiny as it is. Author: Andres Freund
2018-01-26Avoid unnecessary use of pg_strcasecmp for already-downcased identifiers.Tom Lane
We have a lot of code in which option names, which from the user's viewpoint are logically keywords, are passed through the grammar as plain identifiers, and then matched to string literals during command execution. This approach avoids making words into lexer keywords unnecessarily. Some places matched these strings using plain strcmp, some using pg_strcasecmp. But the latter should be unnecessary since identifiers would have been downcased on their way through the parser. Aside from any efficiency concerns (probably not a big factor), the lack of consistency in this area creates a hazard of subtle bugs due to different places coming to different conclusions about whether two option names are the same or different. Hence, standardize on using strcmp() to match any option names that are expected to have been fed through the parser. This does create a user-visible behavioral change, which is that while formerly all of these would work: alter table foo set (fillfactor = 50); alter table foo set (FillFactor = 50); alter table foo set ("fillfactor" = 50); alter table foo set ("FillFactor" = 50); now the last case will fail because that double-quoted identifier is different from the others. However, none of our documentation says that you can use a quoted identifier in such contexts at all, and we should discourage doing so since it would break if we ever decide to parse such constructs as true lexer keywords rather than poor man's substitutes. So this shouldn't create a significant compatibility issue for users. Daniel Gustafsson, reviewed by Michael Paquier, small changes by me Discussion: https://postgr.es/m/29405B24-564E-476B-98C0-677A29805B84@yesql.se
2018-01-19Local partitioned indexesAlvaro Herrera
When CREATE INDEX is run on a partitioned table, create catalog entries for an index on the partitioned table (which is just a placeholder since the table proper has no data of its own), and recurse to create actual indexes on the existing partitions; create them in future partitions also. As a convenience gadget, if the new index definition matches some existing index in partitions, these are picked up and used instead of creating new ones. Whichever way these indexes come about, they become attached to the index on the parent table and are dropped alongside it, and cannot be dropped on isolation unless they are detached first. To support pg_dump'ing these indexes, add commands CREATE INDEX ON ONLY <table> (which creates the index on the parent partitioned table, without recursing) and ALTER INDEX ATTACH PARTITION (which is used after the indexes have been created individually on each partition, to attach them to the parent index). These reconstruct prior database state exactly. Reviewed-by: (in alphabetical order) Peter Eisentraut, Robert Haas, Amit Langote, Jesper Pedersen, Simon Riggs, David Rowley Discussion: https://postgr.es/m/20171113170646.gzweigyrgg6pwsg4@alvherre.pgsql
2018-01-03Clean up tupdesc.c for recent changes.Tom Lane
TupleDescCopy needs to have the same effects as CreateTupleDescCopy in that, since it doesn't copy constraints, it should clear the per-attribute fields associated with them. Oversight in commit cc5f81366. Since TupleDescCopy has already established the presumption that it can just flat-copy the entire attribute array in one go, propagate that approach into CreateTupleDescCopy and CreateTupleDescCopyConstr. (I'm suspicious that this would lead to valgrind complaints if we had any trailing padding in the struct, but we do not, and anyway fixing that seems like a job for a separate commit.) Add some better comments. Thomas Munro, reviewed by Vik Fearing, some additional hacking by me Discussion: https://postgr.es/m/CAEepm=0NvOGZ8B6GbQyQe2C_c2m3LKJ9w=8OMBaYRLgZ_Gw6Nw@mail.gmail.com
2018-01-02Update copyright for 2018Bruce Momjian
Backpatch-through: certain files through 9.3
2017-11-29Update typedefs.list and re-run pgindentRobert Haas
Discussion: http://postgr.es/m/CA+TgmoaA9=1RWKtBWpDaj+sF3Stgc8sHgf5z=KGtbjwPLQVDMA@mail.gmail.com
2017-11-20Parameter toast_tuple_target controls TOAST for new rowsSimon Riggs
Specifies the point at which we try to move long column values into TOAST tables. No effect on existing rows. Discussion: https://postgr.es/m/CANP8+jKsVmw6CX6YP9z7zqkTzcKV1+Uzr3XjKcZW=2Ya00OyQQ@mail.gmail.com Author: Simon Riggs <simon@2ndQudrant.com> Reviewed-by: Andrew Dunstan <andrew.dunstan@2ndQuadrant.com>
2017-11-10Add some const decorations to prototypesPeter Eisentraut
Reviewed-by: Fabien COELHO <coelho@cri.ensmp.fr>
2017-11-08Change TRUE/FALSE to true/falsePeter Eisentraut
The lower case spellings are C and C++ standard and are used in most parts of the PostgreSQL sources. The upper case spellings are only used in some files/modules. So standardize on the standard spellings. The APIs for ICU, Perl, and Windows define their own TRUE and FALSE, so those are left as is when using those APIs. In code comments, we use the lower-case spelling for the C concepts and keep the upper-case spelling for the SQL concepts. Reviewed-by: Michael Paquier <michael.paquier@gmail.com>
2017-10-11Replace remaining uses of pq_sendint with pq_sendint{8,16,32}.Andres Freund
pq_sendint() remains, so extension code doesn't unnecessarily break. Author: Andres Freund Discussion: https://postgr.es/m/20170914063418.sckdzgjfrsbekae4@alap3.anarazel.de
2017-10-11Improve performance of SendRowDescriptionMessage.Andres Freund
There's three categories of changes leading to better performance: - Splitting the per-attribute part of SendRowDescriptionMessage into a v2 and a v3 version allows avoiding branches for every attribute. - Preallocating the size of the buffer to be big enough for all attributes and then using pq_write* avoids unnecessary buffer size checks & resizing. - Reusing a persistently allocated StringInfo for all SendRowDescriptionMessage() invocations avoids repeated allocations & reallocations. Author: Andres Freund Discussion: https://postgr.es/m/20170914063418.sckdzgjfrsbekae4@alap3.anarazel.de
2017-10-11Use one stringbuffer for all rows printed in printtup.c.Andres Freund
This avoids newly allocating, and then possibly growing, the stringbuffer for every row. For wide rows this can substantially reduce memory allocator overhead, at the price of not immediately reducing memory usage after outputting an especially wide row. Author: Andres Freund Discussion: https://postgr.es/m/20170914063418.sckdzgjfrsbekae4@alap3.anarazel.de
2017-09-22For wal_consistency_checking, mask page checksum as well as page LSN.Robert Haas
If the LSN is different, the checksum will be different, too. Ashwin Agrawal, reviewed by Michael Paquier and Kuntal Ghosh Discussion: http://postgr.es/m/CALfoeis5iqrAU-+JAN+ZzXkpPr7+-0OAGv7QUHwFn=-wDy4o4Q@mail.gmail.com
2017-09-14Add support for coordinating record typmods among parallel workers.Andres Freund
Tuples can have type RECORDOID and a typmod number that identifies a blessed TupleDesc in a backend-private cache. To support the sharing of such tuples through shared memory and temporary files, provide a typmod registry in shared memory. To achieve that, introduce per-session DSM segments, created on demand when a backend first runs a parallel query. The per-session DSM segment has a table-of-contents just like the per-query DSM segment, and initially the contents are a shared record typmod registry and a DSA area to provide the space it needs to grow. State relating to the current session is accessed via a Session object reached through global variable CurrentSession that may require significant redesign further down the road as we figure out what else needs to be shared or remodelled. Author: Thomas Munro Reviewed-By: Andres Freund Discussion: https://postgr.es/m/CAEepm=0ZtQ-SpsgCyzzYpsXS6e=kZWqk3g5Ygn3MDV7A8dabUA@mail.gmail.com
2017-08-22Refactor typcache.c's record typmod hash table.Andres Freund
Previously, tuple descriptors were stored in chains keyed by a fixed size array of OIDs. That meant there were effectively two levels of collision chain -- one inside and one outside the hash table. Instead, let dynahash.c look after conflicts for us by supplying a proper hash and equal function pair. This is a nice cleanup on its own, but also simplifies followup changes allowing blessed TupleDescs to be shared between backends participating in parallel query. Author: Thomas Munro Reviewed-By: Andres Freund Discussion: https://postgr.es/m/CAEepm%3D34GVhOL%2BarUx56yx7OPk7%3DqpGsv3CpO54feqjAwQKm5g%40mail.gmail.com