On Saturday 01 July 2006 03:41, Richard Broersma Jr wrote: > > > CHECK ( 1 = ALL ( SELECT COUNT(STATUS) > > > FROM BADGES > > > WHERE STATUS = 'A' > > > GROUP BY EMPNO)) > > > > From the PostgreSQL docs (http://www.postgresql.org/docs/8.1/ > > interactive/sql-createtable.html) > > > > CREATE UNIQUE INDEX one_a_badge_per_employee_idx > > ON badges (empno) > > WHERE status = 'A'; > > http://www.postgresql.org/docs/8.1/interactive/sql-createindex.html > > http://www.postgresql.org/docs/8.1/interactive/indexes-partial.html > > Michael, > > Partial indexs seem to be "what the doctor ordered!" And your suggest is > right on, the idea of the constraint is to allow only one active badge > status at a time. > > But now that I think about it, using the authors suggestion (if it actually > worked), how would would it be possible to change the active status from > one badge to another?
First set status='I' on the one that has status='A', and set status='A' on the one you want. -- Andreas Joseph Krogh <[EMAIL PROTECTED]> Senior Software Developer / Manager gpg public_key: http://dev.officenet.no/~andreak/public_key.asc ------------------------+---------------------------------------------+ OfficeNet AS | The most difficult thing in the world is to | Karenslyst Allé 11 | know how to do a thing and to watch | PO. Box 529 Skøyen | somebody else doing it wrong, without | 0214 Oslo | comment. | NORWAY | | Mobile: +47 909 56 963 | | ------------------------+---------------------------------------------+ ---------------------------(end of broadcast)--------------------------- TIP 5: don't forget to increase your free space map settings
