What will happen at worst if I change the "Number of values" of CCK field

Question

I have a CCK text field and set "Number of values" to a certain number. Now I want to change it to "Unlimited".

It says

Warning! Changing this setting after data has been created could result in the loss of data!

What will happen at worst if I change this? The values of already existing nodes might be really gone as it says? If yes, there is no way to change this to "Unlimited" if I already have some existing nodes?

Answer 1

Changing it to unlimited isn't going to cause an issue. It's a standard warning message for any change on that setting for a field.

So really the only time you would be concerned is if you took an already unlimited field and set it to a static value, which could potentially remove values if the delta of that field on a node exceeded the static value.

Edit: But always be sure to take a backup before doing those kinds of changes, and always do this on a development environment.

Answer 2

I can't think of any reason why you'd suffer any data loss if you're increasing the field's cardinality (I used to do it all the time in D6 and to the best of my recollection nothing ever went wrong).

The problems would start happening if you decreased the cardinality. For example if if it was previously at 3, and you decreased it 2, any nodes that had a 3rd value for that field would lose that data.