Patent ID: 7974942

Claim:
A method for masking data from an original database to produce a masked database, the original database comprising at least one primary data table having at least one target data column, the method comprising: a) copying the primary data table from the original database into a copied database; b) adding a row-identifier column to the primary data table in the copied database to produce a primary row-identifier data table; c) generating a plurality of index values and populating the primary row-identifier column with the index values, wherein each of the index values identifies a row of the primary row-identifier data table; d) for each target data column of the primary row-identifier data table: (i) creating an empty delta data table; (ii) performing a data transformation on the data in the target data column to produce masked data; and (iii) populating the empty delta data table with the masked data and the index values to produce a masked delta data table; and e) merging each of the masked delta data tables produced in step d) (iii) with the primary row-identifier data table to produce a masked primary data table, wherein for each masked delta data table, the merging comprises populating each row of the masked primary data table with masked data from the masked delta data table associated with the index value for a corresponding row.