I think the answer is no.
Hi Ken,
Changing the field display format won't alter the actual value stored in a field, only how it is displayed to the user. The full value will still be stored in the SQL table.
Changing the type or width of a field, or applying or changing constraints on a field, could result in data loss, however.
You may want to set up a secondary field to try this out with.
Usually you will get a warning if there is a chance of data corruption.
If it looks like it will cause problems, What you might want is to set up a workflow to copy the information from the old field to the new field, then delete the old one and rename the new field. You can use the workflow to ensure the change will happen how you want it to appear after the change
As the others have said suggests, some field transitions will cause data loss, some won't.
For example, changing a Text (40 char) to a Number field will cause data loss. Changing a Number to Text (40 chars) won't.
In cases were data loss is inevitable, workflow is a good option, as stated above. Of course, going from text to integer or number is a difficult transition as some fields may contain incompatible data.
In case there are large number of documents in your system, I tend to use SQL to generate reports on fields that will cause problems (such as dollar signs in text fields) and get them sorted early, before using workflow or the SDK to migrate values to the new field.
-Ben
do you know if changing a field contraint from 5 digits to 6 digits will result in loss?
If you try to change from exactly 5 digits required to exactly 6 digits required, you will get an error in the admin console and unable to change the field constraint. If you are using version 9.0+, the error will help you locate the problematic documents.
To successfully make the transition, you could to the following
Alternatively, if you do not have a way to update existing fields, you could leave the constraint as 5 OR 6.