Columnar Database Definition
Columnar databases are database management systems (DBMS) that store data in columns instead of rows.
This storage method shortens the time needed to read and analyze queried data. By storing data in columns, columnar databases can access target data more precisely, rather than scanning and discarding rows of unwanted data. This enables faster disk retrieval, which speeds up performance in the aggregate when massive volumes of data are involved.
Columnar databases are often used as data warehouses. Teams use columnar databases as data warehouses to leverage highly complex queries over vast quantities of data. However, this makes columnar databases less suited for OLTP workloads.