This is not meant to be an exhaustive survey.
Our main interest is to see what kind of bitmap indexing technology is missing and
which technology may likely make an impact on commercial products.
The first commercial product to use the name bitmap index is Model 204. O??™Neil
(1987) has published a description of the indexing method. Model 204 implements
the basic bitmap index. It has no binning or compression. Currently, Model 204 is
marketed by Computer Corporation of America. Oracle has a version of compressed
bitmap indices in its flagship product since version 7.3. They implemented a proprietary
compression method. Based on the observed performance characteristics,
it appears to use equality encoding without binning.
Sybase IQ implements the bit-sliced index (O??™Neil & Quass, 1997). Using the terminology
defined in the second and third sections, Sybase IQ supports unbinned,
binary encoded, uncompressed bitmap indices. In addition, it also has the basic
bitmap index for low-cardinality attributes. IBM DB2 implements a variation of the
binary encoded bitmap index called Encode Vector Index. IBM Informix products
also contain some versions of bitmap indices for queries involving one or more
tables. These indices are specifically designed to speed up join-operations and are
commonly referred to as join indices (O??™Neil & Quass, 1997).
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