Re: Creating a selective aggregate ??
От | Greg Sabino Mullane |
---|---|
Тема | Re: Creating a selective aggregate ?? |
Дата | |
Msg-id | e163eaf2877e3a6b214f2016f5bd8a3c@biglumber.com обсуждение исходный текст |
Ответ на | Creating a selective aggregate ?? ("Najib Abi Fadel" <nabifadel@usj.edu.lb>) |
Список | pgsql-hackers |
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 > I am searching for a way to have the minimum date and maximum > date for dates seperated by one week whitout gaps between them. This is not something you can accomplish (easily) with just SQL, so you will need some sort of higher language. Here's a little function I came up with, which might do what you want: CREATE OR REPLACE FUNCTION noweekgaps() RETURNS SETOF TEXT AS ' DECLARE startday TEXT; endday TEXT; lastone INT; mydiff INT; myrec RECORD; BEGIN FOR myrec IN SELECT TO_CHAR(d, \'Mon DD, YYYY\') AS z, TO_CHAR(d,\'J\')::integer AS j FROM t ORDER BY d ASC LOOP IF startdayIS NULL THEN startday := myrec.z; ELSE mydiff := myrec.j - lastone; IF mydiff > 7 THEN RETURN NEXT startday|| \' - \' || endday; startday := myrec.z; END IF; END IF; lastone := myrec.j; endday := myrec.z; END LOOP; IF endday IS NOT NULL THEN RETURN NEXT startday || \' - \' || endday; END IF; RETURN; END; ' LANGUAGE plpgsql; - -- Greg Sabino Mullane greg@turnstep.com PGP Key: 0x14964AC8 200407031237 -----BEGIN PGP SIGNATURE----- iD8DBQFA5uD9vJuQZxSWSsgRAqpLAKDBm0dxgiigfSL6cnhz83pmKV1KLgCgogD2 etbk3BJiWm5bplCEIEFXbbE= =HT+N -----END PGP SIGNATURE-----
В списке pgsql-hackers по дате отправления: