A column-oriented DBMS (or columnar database) is a database management system (DBMS) that stores data tables as columns rather than as rows. Practical use of a column store versus a row store differs little in the relational DBMS world. Both columnar and row databases use traditional database languages like SQL to load data and perform queries. Both row and columnar databases can become the backbone in a system to serve data for common ETL and data visualization tools. However, by storing data in columns rather than rows, the database can more precisely access the data it needs to answer a query rather than scanning and discarding unwanted data in rows. Query performance is often increased as a result, particularly in very large data sets.