1. A method for performing an incremental refresh of a materialized view defined by a lossless one-to-one join, the method comprising the steps of: establishing a base table of the materialized view as a selected table; if the selected table is the right table of an outer join, then performing the steps of setting to NULL selected columns of rows of the materialized view based on rows of the selected table that have been updated or deleted in the selected table after a prior refresh operation; updating NULL values in selected columns of the materialized view to reflect new values caused by updates and inserts into the selected table that occurred after the prior refresh operation; if the selected table is not the right table of an outer join, then performing the steps of deleting rows from the materialized view based on rows of the selected table that have been updated or deleted in the selected table after the prior refresh operation; and inserting rows into the materialized view based on updates and inserts into the selected table that occurred after the prior refresh operation.