Practice safe Deleting (fields)

[Greg Fong]

I made the mistake of setting a field as a character type when in fact I needed a date type. I was deep into development when I noticed the mistake. The field had already been incorporated into a number of forms. So I went about first backing everything up and then I went through my code to make sure to correct all references to it. I then changed the field type. When I tried to reopen my forms they didn't open. Is there a way to practice safe deleting? Chaulk up another one for backups!

Cheers

[Tom Cone Jr]

RE: Practice safe Deleting (fields)

In similar situations I've:

1) added a new field, of the desired type
2) populated the new field with an update operation, converting the data from the field I want to delete
3) redesigned the existing forms and reports to add the new field, and drop the old one from each
4) finally, restructured the table to delete the old field.

I don't delete the old field until I know the forms and reports will work without it.

(If you think I'm good enough to follow this procedure each and every time, I've got this little piece of slightly damp land down here in Florida I'd like to show you, too!)

-- tom

[forskare]

RE: Practice safe Deleting (fields)

Greg,

Seems strange that this field has such an effect on the forms (w/o know more). Since you've got a backup, no problem.

One thing you can do is to simply change the field from character to date and see what happens.

To answer your question, no, there is no magic formula, at least that I've heard about.

kenn

[forskare]

RE: Practice safe Deleting (fields)

Hi Tom,

I like your advice. As usual, solid as a piece of granite.

kenn

[Lowell Wardlow]

RE: Practice safe Deleting (fields)

Ken - changing the data type of a field is practicaly guaranteed to lose the data. Tom's advice is the best way, I think. Add a new field, run an update using the old field to get the converted value into the new field, test your forms, THEN delete the old field.

Lowell

[forskare]

RE: Practice safe Deleting (fields)

Lowell,

There is no "practically guraenteed to loose data" about it. You WILL lose the data. Tom's suggestion posted while I was writing mine. His advice is pretty much 99.9% pure!!

kenn

[Robert Adler]

RE: Practice safe Deleting (fields)

greg:

Tom's approach is excellent. But you can try a short cut.
1) add a new field, of the desired type
2) populate the new field with an update operation, converting the data from the field you want to delete
3) rename the old field
4) rename the new field to the old field s original name.

5) test the forms to see if the accept the data. if they do. delete the the old renamed field.

this process should avoid modifying forms. If there are calculations involved to character transformations this process is dangerous. And you should stick to Tom's approach.

this is an attempt to reduce time going to each screen.

bob adler