What is a fast method to update filters using a custom field that will be removed?

[Josh Simnitt]

We have several custom fields that will be removed from Jira, and I would like input on a good method to update these filters. 

It looks like it might be possible to use ScriptRunner to update these fields?  I realize that a user could go to the particular filter him/her self and update the filter using the UI.  

I realize that the data also lives in the REQCONTENT field on a Jira table, but I know that generally it's a bad idea to touch that directly.

[Marc Minten (EVS)]

Yes, with scriptrunner you can write a script that

• loops over all (public ?) filters (probably not possible on private filters ?
• get the filter definition
• find out whether the custom field is used (finding its name in the fiter definition)
• take ownership of the filter (the executor of the script needs to have admin rights!)
• change the filter definition
• reset the filter ownership

Of course you "can" also do the changes directly in the database, but then you should at least stop Jira, take a full backup, change, restart Jira and validate your changes did not have any side-effect...