Re: Index usage with Wildcards - Informix vs. Oracle

In <51jjl8$prg@sparcserver.lrz-muenchen.de>, spitz@GANS2X.ana.med.uni-muenchen.de (Richard Spitz) writes: >Hello, > >after a controversial discussion with some colleagues, I want to ask >this question to the collective net wisdom: > >When a query is done using wildcards (e.g. ...WHERE column LIKE 'HUB%'), >can the engine use an existing index on that column? > >To my knowledge, Informix can use the index as long as the wildcard >is not the first character in the query string, as in the above example. > >Our Oracle people claim that Oracle cannot use an index as soon as >wildcards are involved. Is that really true? > >Regards, Richard >-- >+----------------------------+-------------------------------------------+ >| Dr. Richard Spitz | INTERNET: spitz@ana.med.uni-muenchen.de | >| EDV-Gruppe Anaesthesie | Tel : +49-89-7095-3413 | >| Klinikum Grosshadern | FAX : +49-89-7095-8886 | >| 81366 Munich, Germany | | >+----------------------------+-------------------------------------------+ Richard, Oracle behaves in the same way that you have described informix behaving i.e. >To my knowledge, Informix can use the index as long as the wildcard >is not the first character in the query string, as in the above example. Bye, Steve ____________________________________________ | any similarity 'tween my opinions and that | | of my employers are purely hypothetical | | and should give no cause for alarm | --------------------------------------------