A column-oriented DBMS is a database management system (DBMS) that stores data tables as sections of columns of data rather than as rows of data, like most relational DBMSs. This has advantages for data warehouses, customer relationship management (CRM) systems, and library card catalogs, and other ad-hoc inquiry systems where aggregates are computed over large numbers of similar data items.
It is possible to achieve some of the benefits of column-oriented and row-oriented organization with any DBMSs. By denoting one as column-oriented, we are referring to both the ease of expression of a column-oriented structure and the focus on optimizations for column-oriented workloads. This approach is in contrast to row-oriented or row store databases and with correlation databases, which use a value-based storage structure.
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