Re: Foreign key indexing.

Posted in 1994

David I. Berg — 27 Jul 94 00:52:41 GMT — source: Informix-list mailing list archive (1991-1998)

res@expo.din.lois.perm.su (Igor G. Popov, LOIS Ltd.) writes: >Hello, Informixers! >I know, it is helpful to create unique index on primary key and >duplicative index on foreign key. >This is my question: is it useful to create indexes on each >component of the composite foreign key, if there is a composite >index on the hole key already? Unless there is a query that searches or joins on another column in the foreign key, there is no reason to create a separate index on (each of) the other column(s). >Thanks. >. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . >. Igor G. Popov . Laboratory of Open Information Systems, ltd. . >. res@lois.perm.su . Russia, Perm, Kirova 128-770, +7-3422-395028 . >. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ___ ___ Senior Consultant / ) __ . __/ /_ ) _ _ __ Informix Software Inc. (303) 850-0210 _/__/ (_(_ (/ / (_(_ _/__) (-' ~/ '(_- 5299 DTC Blvd #740 Englewood CO 80111 dberg@informix.com Opinions expressed herein are my own.