Disclosed are techniques for increasing the speed of pairwise comparison operations in a database system. In an embodiment, a method is disclosed comprising receiving a network request identifying a user; identifying a plurality of segments associated with the user; loading a plurality of bitmaps associated with the plurality of segments, each bitmap in the plurality of bitmaps representing a set of users associated with a segment; comparing pairs of bitmaps from the plurality of bitmaps to generate a set of overlaps; filtering the plurality of segments based on the set of overlaps to generate an anonymized set of segments; and returning aggregated data associated with the anonymized set of segments in response to the network request.