  A Data Warehouse stores integrated information as materialized views over
data from one or more remote sources. These materialized views must be
maintained in response to actual relation updates in the remote sources. The
data warehouse view maintenance techniques are classified into four major
categories self maintainable recomputation, not self maintainable
recomputation, self maintainable incremental maintenance, and not self
maintainable incremental maintenance. This paper provides a comprehensive
comparison of the techniques in these four categories in terms of the data
warehouse space usage and number of rows accessed in order to propagate an
update from a remote data source to a target materialized view in the data
warehouse.
