Locking Records to Prevent Updates During an Account Import

With respect to importing records into the Accounts module from a CSV file, is it possible to lock certain records in the CRM database to prevent them from being updated if the import file contains erroneously old data? For example let’s say that some prospects have provided correct data (ie correct cellphone, address, postal code, etc). When importing from a CSV, that account may be included in the import file with the old incorrect data that would otherwise overwrite the info already in SuiteCRM’s database.

I was considering creating a field named Rec_Lock. Once prospects records are updated in the database, the user would enter a letter ‘Y’ for those records to prevent the record from being modified by a subsequent account import. When importing records from a CSV file, the system would check the value of Rec_Lock and prevent those records from being modified. Only records with a Rec_Lock field value of ‘N’ could be possibly updated.

Any help / advise would be greatly appreciated. Thanks in advance.