We've had ServiceDesk for a few years. And we've built many Incident templates in it and in Service Catalog. In that time frame we've created a lot of additional fields in both modules that are similar or redundant. I'd like to perform a bit of clean up on fields that can be consolidated. But I do NOT want to lose information on forms that have been submitted and closed. 

For example I have four different date fields being used on four different forms. They are as follows.

I'd like to add the "Effective Date" field to the other three forms for future use and then delete those other three fields as they will no longer be needed. But I need to keep that information they currently hold. So my idea is to add "Effective Date" to each of the three other forms and then have a query ran against the Database that will move or copy data in those fields if there is any to the Effective Date field I added to each form template. Once done, I can delete those three now obsolete fields and have a clean environment. 

I have multiple examples of this though so I'm looking for something where I can identify where info is currently at and where it needs to end up. 

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