DBMS: Bitmap Index/Indexing (Definitions)

"An indexing structure used to provide extremely efficient retrieval. Bitmap indexes are not efficient in update operations, but they work very well in a read-only environment. Microsoft OLAP Services can use bitmap indexes for cubes." (Microsoft Corporation, "Microsoft SQL Server 7.0 Data Warehouse Training Kit", 2000)

"A relational indexing technique most appropriate for columns with a limited number of potential values (low cardinality). Most optimizers can combine more than one bitmapped index in a single query." (Ralph Kimball & Margy Ross, "The Data Warehouse Toolkit 2nd Ed ", 2002)

"An index containing one or more bitmaps." (Peter Gulutzan & Trudy Pelzer, "SQL Performance Tuning", 2002)

"An index that maintains a binary string of ones and zeros for each distinct value of a column within the index." (Bob Bryla, "Oracle Database Foundations", 2004)

"A specialized form of an index indicating the existence or nonexistence of a condition for a group of blocks or records. Bitmaps are expensive to build and maintain, but provide very fast comparison and access facilities." (William H Inmon, "Building the Data Warehouse", 2005)

"An index containing binary representations for each record using 0’s and 1’s. For example, a bitmap index creates two bitmaps for two values of M for Male and F for Female. When M is encountered, the M bitmap is set to 1 and the F bitmap is set to 0." (Gavin Powell, "Beginning Database Design", 2006)

"A compact, high speed indexing method where the key values and the conditions are compressed to a small size that can be stored and searched rapidly." (S. Sumathi & S. Esakkirajan, "Fundamentals of Relational Database Management Systems", 2007)

"An index that uses a bit array (0s and 1s) to represent the existence of a value or condition." (Carlos Coronel et al, "Database Systems: Design, Implementation, and Management" 9th Ed., 2011)

"An indexing technique using a string of zeroes and ones, or bits. For each key value of the bitmap index a separate string of zeroes and ones is stored." (Craig S Mullins, "Database Administration: The Complete Guide to DBA Practices and Procedures", 2012)

"A subcomponent of a single bitmap index entry. Each indexed column value may have one or more bitmap pieces. The database uses bitmap pieces to break up an index entry that is large in relation to the size of a block." (Oracle, "Database SQL Tuning Guide Glossary", 2013)