Re: Table design question

Mark Stock wrote: >Tino Cremidis wrote: >> >> Don: >> >> Once I worked with a pharmacy system that created a key based on >> three caracters from the last name, three characters from >> the first name, a number based on a very simple hashing algoritm >> based on the full name and for duplicates a sequence number. snip >> With this approach queries, are simpler and the user does not have >> to remember a key, you build it at query time. If more than one >> client matched First and Last name you simply show a pick list and >> let the user pick the right one. > >I thought this approach went out with the mainframes. With QBE the user >doesn't have to remember a key. Also the code is simpler. Besides which, if you still want this it is simple to allow the user to enter those six letters and then turn it into a QBE for your query; you wouldn't even have to store the silly thing in an index. On top of this you STILL have a smaller key with serial; your approach requires 6 bytes plus whatever you require for the unique number. Stick with serial. David