Re: Pattern search + Shift AND Algorithm

In article <3oe6nv$s5o@cssun.mathcs.emory.edu>, nnob@loc.gov (Nick Nobbe) wrote: >On Thu, 4 May 1995, Michael Jatzeck wrote: > >> Hello, >> >> I am confronted with a usual problem in database applications: I have to >> prevent the users from inserting items more than once. The primary key of this >> item is a text string, therefore my first choice was the Shift-AND algorithm >> by S.Wu and U. Manbar to find rows with a similar key before entering a new >> one. >> >----- stuff deleted ----- > > Michael, > Hey, wait a minute! Did you say you want to prevent your users from > entering a duplicate key. How can that be if the key is unique? > Why bother if you can trap the error condition and return a message, or > if the users are using Isql, they will most likely receive an Informix > error message. > Begging you forgiveness for my fuzzy thinking, but it is late Friday > afternoon over here. Well the point is, that this text string contains the name of a real person. Therefore it might be mispelled by the user. What I want to prevent is that multiple records are inserted for the same person. Of course you cannot prevent a user from inserting the above kind of duplicate record if he wants to. But you can provide the user with a list of similar entries so that he at least knows about them and can choose by himself. This is I want to use the Shift AND alg. for. Yours, Michael __________ _/_/_/_/_/ _/_/_/_/ _/_/_/_/ Michael Jatzeck michel@taz.de _/ _/ _/ _/ die tageszeitung _/ _/_/_/_/ _/ Germany _/ _/ _/ _/ D-10969 Berlin Phone: +49-30-25902-131 _/ _/ _/ _/_/_/_/ Kochstr. 18 FAX : +49-30-2510694