Bitmap indexes are tailored to data warehouses.The bitmap index has an interesting history. According to the book: Database Systems - The Complete Book from Jeffrey Ullman (Professor of Computer Science at Stanford University):
In its simplest form, a bitmap index on an index consists of one vector of bits (i.e., bitmap) per attribute value, where the size of each bitmap is equal to the number of records in the indexed relation. For example, if the attribute is day of the week, then there would be seven bitmap vectors for that attribute, one for each day. The bitmap vector corresponding to Monday would have a 1 at position i if record i contains Monday in the day-of-week attribute. This approach is called a value-list index.
There was a company called Nucleus, founded by Ted Glaser that patented the idea and developed a DBMS in which the bitmap index was both the index structure and the data representation. The company failed in the late 1980's, but the idea has recently incorporated into several major commercial database systems.But according to other sources: Data Warehouse Tuning: What's Different About Data Warehouses
These indexes have already been used in some commercial products to speed up query processing: the main early example was Model 204, a prerelational DBMS from Computer Corporation of America.and VLDB Vision - How the VLDB scene has changed
Bitmap indexes were introduced to the market in the 1970s by Computer Corporation of America (www.cca-int.com) in Model 204, a DBMS for the mainframe. Still around and still delivering astonishingly good performance in predicate evaluation and other areas, Model 204 undoubtedly features the most mature, and probably the best integrated, implementation of bitmap indexes. Of all the database engines on the market, it alone was designed to use bitmap indexes from the beginning.Computer Corporation of America (CCA) was founded in 1965. More info about the company you can read on its company's home page. More info about the 204 model you can read here:
Bitmap indexes were first developed for database use in the Model 204 product from Computer Corporation of America.Another interesting finding related to the bitmap indexes subject is a patent of Oracle Corporation from 2001 year: Supporting bitmap indexes on primary B+tree like structures (Short Description, Detailed Description)
Bert Scalzo has published an interesting article in Linux Journal that compares the performance of non-RAC Linux systems, which are using the new Oracle 10g feature - ASM versus using of Linux filesystems: Optimizing Oracle 10g on Linux: Non-RAC ASM vs. LVM