postgres

Commit Graph

Author	SHA1	Message	Date
Alvaro Herrera	bc085205c8	Change CREATE STATISTICS syntax 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	9 years ago
Alvaro Herrera	ee6922112e	Rename columns in new pg_statistic_ext catalog 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	9 years ago
Alvaro Herrera	7b504eb282	Implement multivariate n-distinct coefficients 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	9 years ago
Tom Lane	18555b1323	Establish conventions about global object names used in regression tests. To ensure that "make installcheck" can be used safely against an existing installation, we need to be careful about what global object names (database, role, and tablespace names) we use; otherwise we might accidentally clobber important objects. There's been a weak consensus that test databases should have names including "regression", and that test role names should start with "regress_", but we didn't have any particular rule about tablespace names; and neither of the other rules was followed with any consistency either. This commit moves us a long way towards having a hard-and-fast rule that regression test databases must have names including "regression", and that test role and tablespace names must start with "regress_". It's not completely there because I did not touch some test cases in rolenames.sql that test creation of special role names like "session_user". That will require some rethinking of exactly what we want to test, whereas the intent of this patch is just to hit all the cases in which the needed renamings are cosmetic. There is no enforcement mechanism in this patch either, but if we don't add one we can expect that the tests will soon be violating the convention again. Again, that's not such a cosmetic change and it will require discussion. (But I did use a quick-hack enforcement patch to find these cases.) Discussion: <16638.1468620817@sss.pgh.pa.us>	10 years ago
Robert Haas	bc4996e61b	Make ALTER .. SET SCHEMA do nothing, instead of throwing an ERROR. This was already true for CREATE EXTENSION, but historically has not been true for other object types. Therefore, this is a backward incompatibility. Per discussion on pgsql-hackers, everyone seems to agree that the new behavior is better. Marti Raudsepp, reviewed by Haribabu Kommi and myself	10 years ago
Tom Lane	5516549770	Fix some typos in regression test comments. Back-patch to avoid unnecessary cross-branch differences. CharSyam	11 years ago
Peter Eisentraut	001e114b8d	Fix whitespace issues found by git diff --check, add gitattributes Set per file type attributes in .gitattributes to fine-tune whitespace checks. With the associated cleanups, the tree is now clean for git	12 years ago
Robert Haas	e6055061c5	Additional regression tests for ALTER OPERATOR FAMILY. Robins Tharakan, reviewed by Szymon Guz	13 years ago
Alvaro Herrera	765cbfdc92	Refactor ALTER some-obj RENAME implementation Remove duplicate implementations of catalog munging and miscellaneous privilege checks. Instead rely on already existing data in objectaddress.c to do the work. Author: KaiGai Kohei, changes by me Reviewed by: Robert Haas, Álvaro Herrera, Dimitri Fontaine	13 years ago
Alvaro Herrera	ece26987c2	Remove collations from generic ALTER test The error messages they generate are not portable enough. Also, since the only point of the alter_generic_1 expected file was to cover platforms with no collation support, it's now useless, so remove it.	13 years ago
Alvaro Herrera	ff7e5b4841	Add alter_generic regression test This makes refactoring of parts of the ALTER command safe(r) because we ensure no change in functionality. Author: KaiGai Kohei	13 years ago

11 Commits (bc085205c8a425fcaa54e27c6dcd83101130439b)