Abstract: OLAP uses multidimensional structures, to provide
access to data for analysis. Traditionally, OLAP operations are more
focused on retrieving data from a single data mart. An exception is
the drill across operator. This, however, is restricted to retrieving
facts on common dimensions of the multiple data marts. Our concern
is to define further operations while retrieving data from multiple
data marts. Towards this, we have defined six operations which
coalesce data marts. While doing so we consider the common as well
as the non-common dimensions of the data marts.