7 Commits (cf5ec3d12bcbd7ead3fd3f35ed94ef31c751e275)

Author	SHA1	Message	Date
Bruce Momjian	64d0b8b05f	Attached is an update to contrib/tablefunc. It implements a new hashed ... version of crosstab. This fixes a major deficiency in real-world use of the original version. Easiest to undestand with an illustration: Data: ------------------------------------------------------------------- select * from cth; id | rowid | rowdt | attribute | val ----+-------+---------------------+----------------+--------------- 1 | test1 | 2003-03-01 00:00:00 | temperature | 42 2 | test1 | 2003-03-01 00:00:00 | test_result | PASS 3 | test1 | 2003-03-01 00:00:00 | volts | 2.6987 4 | test2 | 2003-03-02 00:00:00 | temperature | 53 5 | test2 | 2003-03-02 00:00:00 | test_result | FAIL 6 | test2 | 2003-03-02 00:00:00 | test_startdate | 01 March 2003 7 | test2 | 2003-03-02 00:00:00 | volts | 3.1234 (7 rows) Original crosstab: ------------------------------------------------------------------- SELECT * FROM crosstab( 'SELECT rowid, attribute, val FROM cth ORDER BY 1,2',4) AS c(rowid text, temperature text, test_result text, test_startdate text, volts text); rowid | temperature | test_result | test_startdate | volts -------+-------------+-------------+----------------+-------- test1 | 42 | PASS | 2.6987 | test2 | 53 | FAIL | 01 March 2003 | 3.1234 (2 rows) Hashed crosstab: ------------------------------------------------------------------- SELECT * FROM crosstab( 'SELECT rowid, attribute, val FROM cth ORDER BY 1', 'SELECT DISTINCT attribute FROM cth ORDER BY 1') AS c(rowid text, temperature int4, test_result text, test_startdate timestamp, volts float8); rowid | temperature | test_result | test_startdate | volts -------+-------------+-------------+---------------------+-------- test1 | 42 | PASS | | 2.6987 test2 | 53 | FAIL | 2003-03-01 00:00:00 | 3.1234 (2 rows) Notice that the original crosstab slides data over to the left in the result tuple when it encounters missing data. In order to work around this you have to be make your source sql do all sorts of contortions (cartesian join of distinct rowid with distinct attribute; left join that back to the real source data). The new version avoids this by building a hash table using a second distinct attribute query. The new version also allows for "extra" columns (see the README) and allows the result columns to be coerced into differing datatypes if they are suitable (as shown above). In testing a "real-world" data set (69 distinct rowid's, 27 distinct categories/attributes, multiple missing data points) I saw about a 5-fold improvement in execution time (from about 2200 ms old, to 440 ms new). I left the original version intact because: 1) BC, 2) it is probably slightly faster if you know that you have no missing attributes. README and regression test adjustments included. If there are no objections, please apply. Joe Conway	23 years ago
Tom Lane	1f1c332381	Remove inappropriate double-quoting in connectby() code; adjust ... regression test to avoid using VALUE as a name. From Joe Conway.	23 years ago
Bruce Momjian	e5cf1a8a26	SET autocommit no longer needed in /contrib because pg_regress.sh does ... it automatically now on regression session startup.	24 years ago
Bruce Momjian	aa4c702eac	Update /contrib for "autocommit TO 'on'". ... Create objects in public schema. Make spacing/capitalization consistent. Remove transaction block use for object creation. Remove unneeded function GRANTs.	24 years ago
Bruce Momjian	a62873d279	The attached adds a bit to the contrib/tablefunc regression test for ... behavior of connectby() in the presence of infinite recursion. Please apply this one in addition to the one sent earlier. Joe Conway	24 years ago
Tom Lane	bd04184b11	Attached is a patch to fix some recently raised issues that exist in ... contrib/tablefunc. Specifically it replaces the use of VIEWs (for needed composite type creation) with use of CREATE TYPE. It also performs GRANT EXECUTE ON FUNCTION foo() TO PUBLIC for all of the created functions. There was also a cosmetic change to two regression files. Joe Conway	24 years ago
Bruce Momjian	6fff9a7475	The attached removes the current non-standard file ... "contrib/tablefunc/tablefunc-test.sql", and adds a standard regression test suite to contrib/tablefunc. Joe Conway	24 years ago