The “Merge duplicates into record with most populated fields” is the choice that best suits our need for resolving Duplicate Customers (per the duplicate detection rule); however, I would like to retain each email address that we have for that customer on one record. (i.e. The main email would be maintained from the “record with most populated fields” and all other email addresses would be saved on that merged record as alternates.)
Does this make sense; is this doable?
It does make sense. It’s not really doable within the duplicate entity management function. When you merge records it’ll only keep data for the same field that is blank on the “master” record (in this case those with the most populated fields). There are some other merging options, see “Submitting Merge Operations” SuiteAnswer Id: 48694, but I don’t think any of them are really going to do what you’re describing.
In your particular case, I’d probably create some saved searches to pull out all the customer emails (and any other data you definitely want to keep from all records). Then do the merge however you want to do it. Then do a CSV import to load the data into the merged customer record (probably as an associated Contact record). This will probably require some Excel ninjaing, to get to a good end result. Probably a good idea to test it out with a few particular records/duplicate sets (or in sandbox) before processing the whole thing.
Also be aware that NetSuite is a little funky in how it calculates the “most populated fields”. The only fields counted are Standard Entity Fields, and there are some Fields especially under Financial tab that are not counted. Also, the Address Fields in the Address form, Address ID and Address field in the Customer form are counted individually. So keep that in mind when considering your merge selection.