update database?

How are database updates for applications done commercially?

I am looking for some guidelines on how to save my clients existing data and at the same time update the database with new fields.

Any ideas or thoughts greatly appreciated. :)

As you are talking about new fields, the existing data should not be affected unless you are planning on taking data in existing fields, and moving it to one or more of the new fields. That gets to be a pain.

However, if all you are doing it adding new fields, then do a complete backup of the database (this is just to be one the safe side). Verify the backup is solid.

Then, just add your new fields. It shouldn't have any affect on the existing data at all, but, if something odd happens, you can always do a restore.

Yes, all I want to do is create a new table and update or add 2 fields to an existing table. I did some research and learned about Create Table and Alter Table and have this thread going http://www.vbforums.com/showthread.p...7&goto=newpost

I know this post is a couple months old but I have another database update question. I need to know the best way to do this:

My client is adding new bio information to existing bios, adding new individual bios and deleting bios. So the table Bios is changing.

Whats the best way to accomplish this?

Should I delete the old bios table in the existing database and add a new updated table? This seems to me to be the bestway.

Any advice?

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I am not sure why I even asked this question. I'll just use SQL insert statements and delete statments where I need them.

Problem solved.

If you are using SQL then adding a NEW field should be no problem unless it is really not a new field but a field replacing another.