Data conversion is one of the most critical phases of moving to a new database. It can also be the costliest and may lead to unexpected expenses. It is thus important to convert as little as possible. Data should always be cleaned before conversion. For example, open invoices should be converted as static data. For small data sets, you should use manual data entry for small sets of data. If you have over 1,000 records of a particular subset of data, it is often easier to write a conversion script.”]
Source: https://gbhackers.com/tips-for-successful-data-conversion-to-improve-accuracy/