11 Commits (d02cceb85cf1a46a36c36825dd8266a30aed134f)

Author	SHA1	Message	Date
Tom Lane	0ec5f7e782	Allow subscripting of hstore values. ... This is basically a finger exercise to prove that it's possible for an extension module to add subscripting ability. Subscripted fetch from an hstore is not different from the existing "hstore -> text" operator. Subscripted update does seem to be a little easier to use than the traditional update method using hstore concatenation, but it's not a fundamentally new ability. However, there may be some value in the code as sample code, since it shows what's basically the minimum-complexity way to implement subscripting when one needn't consider nested container objects. Discussion: https://postgr.es/m/3724341.1607551174@sss.pgh.pa.us	5 years ago
Alexander Korotkov	911e702077	Implement operator class parameters ... PostgreSQL provides set of template index access methods, where opclasses have much freedom in the semantics of indexing. These index AMs are GiST, GIN, SP-GiST and BRIN. There opclasses define representation of keys, operations on them and supported search strategies. So, it's natural that opclasses may be faced some tradeoffs, which require user-side decision. This commit implements opclass parameters allowing users to set some values, which tell opclass how to index the particular dataset. This commit doesn't introduce new storage in system catalog. Instead it uses pg_attribute.attoptions, which is used for table column storage options but unused for index attributes. In order to evade changing signature of each opclass support function, we implement unified way to pass options to opclass support functions. Options are set to fn_expr as the constant bytea expression. It's possible due to the fact that opclass support functions are executed outside of expressions, so fn_expr is unused for them. This commit comes with some examples of opclass options usage. We parametrize signature length in GiST. That applies to multiple opclasses: tsvector_ops, gist__intbig_ops, gist_ltree_ops, gist__ltree_ops, gist_trgm_ops and gist_hstore_ops. Also we parametrize maximum number of integer ranges for gist__int_ops. However, the main future usage of this feature is expected to be json, where users would be able to specify which way to index particular json parts. Catversion is bumped. Discussion: https://postgr.es/m/d22c3a18-31c7-1879-fc11-4c1ce2f5e5af%40postgrespro.ru Author: Nikita Glukhov, revised by me Reviwed-by: Nikolay Shaplov, Robert Haas, Tom Lane, Tomas Vondra, Alvaro Herrera	6 years ago
Tom Lane	eb67623c96	Mark some contrib modules as "trusted". ... This allows these modules to be installed into a database without superuser privileges (assuming that the DBA or sysadmin has installed the module's files in the expected place). You only need CREATE privilege on the current database, which by default would be available to the database owner. The following modules are marked trusted: btree_gin btree_gist citext cube dict_int earthdistance fuzzystrmatch hstore hstore_plperl intarray isn jsonb_plperl lo ltree pg_trgm pgcrypto seg tablefunc tcn tsm_system_rows tsm_system_time unaccent uuid-ossp In the future we might mark some more modules trusted, but there seems to be no debate about these, and on the whole it seems wise to be conservative with use of this feature to start out with. Discussion: https://postgr.es/m/32315.1580326876@sss.pgh.pa.us	6 years ago
Tom Lane	eb6f29141b	Add a 64-bit hash function for type hstore. ... There's some question about the correctness of the hash function, but if it's wrong, the 32-bit version is also wrong. Amul Sul, reviewed by Hironobu Suzuki Discussion: https://postgr.es/m/CAAJ_b947JjnNr9Cp45iNjSqKf6PA5mCTmKsRwPjows93YwQrmw@mail.gmail.com	7 years ago
Tom Lane	7d08ce286c	Distinguish selectivity of < from <= and > from >=. ... Historically, the selectivity functions have simply not distinguished < from <=, or > from >=, arguing that the fraction of the population that satisfies the "=" aspect can be considered to be vanishingly small, if the comparison value isn't any of the most-common-values for the variable. (If it is, the code path that executes the operator against each MCV will take care of things properly.) But that isn't really true unless we're dealing with a continuum of variable values, and in practice we seldom are. If "x = const" would estimate a nonzero number of rows for a given const value, then it follows that we ought to estimate different numbers of rows for "x < const" and "x <= const", even if the const is not one of the MCVs. Handling this more honestly makes a significant difference in edge cases, such as the estimate for a tight range (x BETWEEN y AND z where y and z are close together). Hence, split scalarltsel into scalarltsel/scalarlesel, and similarly split scalargtsel into scalargtsel/scalargesel. Adjust <= and >= operator definitions to reference the new selectivity functions. Improve the core ineq_histogram_selectivity() function to make a correction for equality. (Along the way, I learned quite a bit about exactly why that function gives good answers, which I tried to memorialize in improved comments.) The corresponding join selectivity functions were, and remain, just stubs. But I chose to split them similarly, to avoid confusion and to prevent the need for doing this exercise again if someone ever makes them less stubby. In passing, change ineq_histogram_selectivity's clamp for extreme probability estimates so that it varies depending on the histogram size, instead of being hardwired at 0.0001. With the default histogram size of 100 entries, you still get the old clamp value, but bigger histograms should allow us to put more faith in edge values. Tom Lane, reviewed by Aleksander Alekseev and Kuntal Ghosh Discussion: https://postgr.es/m/12232.1499140410@sss.pgh.pa.us	8 years ago
Tom Lane	749a787c5b	Handle contrib's GIN/GIST support function signature changes honestly. ... In commits 9ff60273e3 and dbe2328959 I (tgl) fixed the signatures of a bunch of contrib's GIN and GIST support functions so that they would pass validation by the recently-added amvalidate functions. The backend does not actually consult or check those signatures otherwise, so I figured this was basically cosmetic and did not require an extension version bump. However, Alexander Korotkov pointed out that that would leave us in a pretty messy situation if we ever wanted to redefine those functions later, because there wouldn't be a unique way to name them. Since we're going to be bumping these extensions' versions anyway for parallel-query cleanups, let's take care of this now. Andreas Karlsson, adjusted for more search-path-safety by me	9 years ago
Andrew Dunstan	d9134d0a35	Introduce jsonb, a structured format for storing json. ... The new format accepts exactly the same data as the json type. However, it is stored in a format that does not require reparsing the orgiginal text in order to process it, making it much more suitable for indexing and other operations. Insignificant whitespace is discarded, and the order of object keys is not preserved. Neither are duplicate object keys kept - the later value for a given key is the only one stored. The new type has all the functions and operators that the json type has, with the exception of the json generation functions (to_json, json_agg etc.) and with identical semantics. In addition, there are operator classes for hash and btree indexing, and two classes for GIN indexing, that have no equivalent in the json type. This feature grew out of previous work by Oleg Bartunov and Teodor Sigaev, which was intended to provide similar facilities to a nested hstore type, but which in the end proved to have some significant compatibility issues. Authors: Oleg Bartunov, Teodor Sigaev, Peter Geoghegan and Andrew Dunstan. Review: Andres Freund	12 years ago
Andrew Dunstan	a18167510f	Use a new hstore extension version for added json functions. ... This should have been done when the json functionality was added to hstore in 9.3.0. To handle this correctly, the upgrade script therefore uses conditional logic by using plpgsql in a DO statement to add the two new functions and the new cast. If hstore_to_json_loose is detected as already present and dependent on the hstore extension nothing is done. This will require that the database be loaded with plpgsql. People who have installed the earlier and spurious 1.1 version of hstore will need to do: ALTER EXTENSION hstore UPDATE; to pick up the new functions properly.	12 years ago
Robert Haas	b60653bc0b	Remove hstore's text => text operator. ... Since PostgreSQL 9.0, we've emitted a warning message when an operator named => is created, because the SQL standard now reserves that token for another use. But we've also shipped such an operator with hstore. Use of the function hstore(text, text) has been recommended in preference to =>(text, text). Per discussion, it's now time to take the next step and stop shipping the operator. This will allow us to prohibit the use of => as an operator name in a future release if and when we wish to support the SQL standard use of this token. The release notes should mention this incompatibility. Patch by me, reviewed by David Wheeler, Dimitri Fontaine and Tom Lane.	14 years ago
Tom Lane	f5fc1de501	Bring hstore's comment into line with style of other contrib comments. ... All the other ones that are primarily a new datatype say "data type for <purpose>", so make this one similar.	15 years ago
Tom Lane	629b3af27d	Convert contrib modules to use the extension facility. ... This isn't fully tested as yet, in particular I'm not sure that the "foo--unpackaged--1.0.sql" scripts are OK. But it's time to get some buildfarm cycles on it. sepgsql is not converted to an extension, mainly because it seems to require a very nonstandard installation process. Dimitri Fontaine and Tom Lane	15 years ago