View Full Version : Increase field size in RDB


Don Eric
08-09-2009, 11:05 PM
Hi guys,

This is a really inane question, but how can I increase a field size (from 50 to 255) within a table when it is part of numerous relationships without jeopardising all the relationships?

In the past I have delete relationship links and then make corrections and put the relationships back, but I only did this in small experimental databases and I am concerned that if I delete the relationship in my new (more complex database) it might screw up all the other data as there are subforms, lookups etc in place.

Can anyone suggest the safest way for me to increase the field size?

cheers, Don

Galaxiom
08-09-2009, 11:22 PM
Extract all the relationship information using vba before you make the changes and reapply it afterwards.

Don Eric
08-09-2009, 11:30 PM
Thanks for that Galaxiom. Unfortunately that's well above my head. Just hypothetically, if I were to remove the relationship links and make my field size change and then put the links back, would it screw up all the lookups, queries etc :confused:

Galaxiom
08-09-2009, 11:39 PM
So long as you put them back you won't have any problem.
Sort them into a nice chart and print it out. (Print screen works for this)

The main ones to get right are the Referential Integrity relationships.
Get these wrong and there will be trouble.

AFAIK the ordinary relationships don't actually have direct effect on a queries as the relationship is crystallised in the join when the query is created.

Likewise with the lookups.

Don Eric
08-09-2009, 11:44 PM
Thanks mate. I will give it a shot.