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* 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
* Fix violations of CatalogTupleInsert/Update/Delete abstraction.Tom Lane2017-06-14
| | | | | | | | | | | | | | | In commits 2f5c9d9c9 and ab0289651 we invented an abstraction layer to insulate catalog manipulations from direct heap update calls. But evidently some patches that hadn't landed in-tree at that point didn't get the memo completely. Fix a couple of direct calls to simple_heap_delete to use CatalogTupleDelete instead; these appear to have been added in commits 7c4f52409 and 7b504eb28. This change is purely cosmetic ATM, but there's no point in having an abstraction layer if we allow random code to break it. Masahiko Sawada and Tom Lane Discussion: https://postgr.es/m/CAD21AoDOPRSVcwbnCN3Y1n_68ATyTspsU6=ygtHz_uY0VcdZ8A@mail.gmail.com
* Post-PG 10 beta1 pgindent runBruce Momjian2017-05-17
| | | | perltidy run not included.
* Fix handling of extended statistics during ALTER COLUMN TYPE.Tom Lane2017-05-14
| | | | | | | | | | | | | | | | | | | | | | | ALTER COLUMN TYPE on a column used by a statistics object fails since commit 928c4de30, because the relevant switch in ATExecAlterColumnType is unprepared for columns to have dependencies from OCLASS_STATISTIC_EXT objects. Although the existing types of extended statistics don't actually need us to do any work for a column type change, it seems completely indefensible that that assumption is hidden behind the failure of an unrelated module to contain any code for the case. Hence, create and call an API function in statscmds.c where the assumption can be explained, and where we could add code to deal with the problem when it inevitably becomes real. Also, the reason this wasn't handled before, neither for extended stats nor for the last half-dozen new OCLASS kinds :-(, is that the default: in that switch suppresses compiler warnings, allowing people to miss the need to consider it when adding an OCLASS. We don't really need a default because surely getObjectClass should only return valid values of the enum; so remove it, and add the missed OCLASS entries where they should be. Discussion: https://postgr.es/m/20170512221010.nglatgt5azzdxjlj@alvherre.pgsql
* Standardize terminology for pg_statistic_ext entries.Tom Lane2017-05-14
| | | | | | | | | | | | | | | | | | | | | Consistently refer to such an entry as a "statistics object", not just "statistics" or "extended statistics". Previously we had a mismash of terms, accompanied by utter confusion as to whether the term was singular or plural. That's not only grating (at least to the ear of a native English speaker) but could be outright misleading, eg in error messages that seemed to be referring to multiple objects where only one could be meant. This commit fixes the code and a lot of comments (though I may have missed a few). I also renamed two new SQL functions, pg_get_statisticsextdef -> pg_get_statisticsobjdef pg_statistic_ext_is_visible -> pg_statistics_obj_is_visible to conform better with this terminology. I have not touched the SGML docs other than fixing those function names; the docs certainly need work but it seems like a separable task. Discussion: https://postgr.es/m/22676.1494557205@sss.pgh.pa.us
* Fix dependencies for extended statistics objects.Tom Lane2017-05-12
| | | | | | | | | | | | | | | | | | | | A stats object ought to have a dependency on each individual column it reads, not the entire table. Doing this honestly lets us get rid of the hard-wired logic in RemoveStatisticsExt, which seems to have been misguidedly modeled on RemoveStatistics; and it will be far easier to extend to multiple tables later. Also, add overlooked dependency on owner, and make the dependency on schema be NORMAL like every other such dependency. There remains some unfinished work here, which is to allow statistics objects to be extension members. That takes more effort than just adding the dependency call, though, so I left it out for now. initdb forced because this changes the set of pg_depend records that should exist for a statistics object. Discussion: https://postgr.es/m/22676.1494557205@sss.pgh.pa.us
* Change CREATE STATISTICS syntaxAlvaro Herrera2017-05-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Previously, we had the WITH clause in the middle of the command, where you'd specify both generic options as well as statistic types. Few people liked this, so this commit changes it to remove the WITH keyword from that clause and makes it accept statistic types only. (We currently don't have any generic options, but if we invent in the future, we will gain a new WITH clause, probably at the end of the command). Also, the column list is now specified without parens, which makes the whole command look more similar to a SELECT command. This change will let us expand the command to supporting expressions (not just columns names) as well as multiple tables and their join conditions. Tom added lots of code comments and fixed some parts of the CREATE STATISTICS reference page, too; more changes in this area are forthcoming. He also fixed a potential problem in the alter_generic regression test, reducing verbosity on a cascaded drop to avoid dependency on message ordering, as we do in other tests. Tom also closed a security bug: we documented that table ownership was required in order to create a statistics object on it, but didn't actually implement it. Implement tab-completion for statistics objects. This can stand some more improvement. Authors: Alvaro Herrera, with lots of cleanup by Tom Lane Discussion: https://postgr.es/m/20170420212426.ltvgyhnefvhixm6i@alvherre.pgsql
* Code review for commands/statscmds.c.Tom Lane2017-04-24
| | | | | | | | | | | | | | | | | | | | Fix machine-dependent sorting of column numbers. (Odd behavior would only materialize for column numbers above 255, but that's certainly legal.) Fix poor choice of SQLSTATE for some errors, and improve error message wording. (Notably, "is not a scalar type" is a totally misleading way to explain "does not have a default btree opclass".) Avoid taking AccessExclusiveLock on the associated relation during DROP STATISTICS. That's neither necessary nor desirable, and it could easily have put us into situations where DROP fails (compare commit 68ea2b7f9). Adjust/improve comments. David Rowley and Tom Lane Discussion: https://postgr.es/m/CAKJS1f-GmCfPvBbAEaM5xoVOaYdVgVN1gicALSoYQ77z-+vLbw@mail.gmail.com
* Rename columns in new pg_statistic_ext catalogAlvaro Herrera2017-04-17
| | | | | | | | | The new catalog reused a column prefix "sta" from pg_statistic, but this is undesirable, so change the catalog to use prefix "stx" instead. Also, rename the column that lists enabled statistic kinds as "stxkind" rather than "enabled". Discussion: https://postgr.es/m/CAKJS1f_2t5jhSN7huYRFH3w3rrHfG2QU7hiUHsu-Vdjd1rYT3w@mail.gmail.com
* Tighten up relation kind checks for extended statisticsAlvaro Herrera2017-04-17
| | | | | | | | | | | | We were accepting creation of extended statistics only for regular tables, but they can usefully be created for foreign tables, partitioned tables, and materialized views, too. Allow those cases. While at it, make sure all the rejected cases throw a consistent error message, and add regression tests for the whole thing. Author: David Rowley, Álvaro Herrera Discussion: https://postgr.es/m/CAKJS1f-BmGo410bh5RSPZUvOO0LhmHL2NYmdrC_Jm8pk_FfyCA@mail.gmail.com
* Reduce lock level for CREATE STATISTICSSimon Riggs2017-04-05
| | | | | | In line with other lock reductions related to planning. Simon Riggs
* Collect and use multi-column dependency statsSimon Riggs2017-04-05
| | | | | | | | | | | | | | | | | | Follow on patch in the multi-variate statistics patch series. CREATE STATISTICS s1 WITH (dependencies) ON (a, b) FROM t; ANALYZE; will collect dependency stats on (a, b) and then use the measured dependency in subsequent query planning. Commit 7b504eb282ca2f5104b5c00b4f05a3ef6bb1385b added CREATE STATISTICS with n-distinct coefficients. These are now specified using the mutually exclusive option WITH (ndistinct). Author: Tomas Vondra, David Rowley Reviewed-by: Kyotaro HORIGUCHI, Álvaro Herrera, Dean Rasheed, Robert Haas and many other comments and contributions Discussion: https://postgr.es/m/56f40b20-c464-fad2-ff39-06b668fac47c@2ndquadrant.com
* Fix use-after-free bugAlvaro Herrera2017-03-24
| | | | Detected by buildfarm member prion
* Implement multivariate n-distinct coefficientsAlvaro Herrera2017-03-24
Add support for explicitly declared statistic objects (CREATE STATISTICS), allowing collection of statistics on more complex combinations that individual table columns. Companion commands DROP STATISTICS and ALTER STATISTICS ... OWNER TO / SET SCHEMA / RENAME are added too. All this DDL has been designed so that more statistic types can be added later on, such as multivariate most-common-values and multivariate histograms between columns of a single table, leaving room for permitting columns on multiple tables, too, as well as expressions. This commit only adds support for collection of n-distinct coefficient on user-specified sets of columns in a single table. This is useful to estimate number of distinct groups in GROUP BY and DISTINCT clauses; estimation errors there can cause over-allocation of memory in hashed aggregates, for instance, so it's a worthwhile problem to solve. A new special pseudo-type pg_ndistinct is used. (num-distinct estimation was deemed sufficiently useful by itself that this is worthwhile even if no further statistic types are added immediately; so much so that another version of essentially the same functionality was submitted by Kyotaro Horiguchi: https://postgr.es/m/20150828.173334.114731693.horiguchi.kyotaro@lab.ntt.co.jp though this commit does not use that code.) Author: Tomas Vondra. Some code rework by Álvaro. Reviewed-by: Dean Rasheed, David Rowley, Kyotaro Horiguchi, Jeff Janes, Ideriha Takeshi Discussion: https://postgr.es/m/543AFA15.4080608@fuzzy.cz https://postgr.es/m/20170320190220.ixlaueanxegqd5gr@alvherre.pgsql