A column-oriented database, or columnar database, stores data in columns rather than rows. Columnar databases are designed to be efficient and fast for analytics workflows. They are optimized for reading and computing on columns efficiently. Columnar databases have several advantages: They can reduce data storage costs. They can improve query performance. They can significantly reduce the amount of disk space required to store data.
Bigtable, Cassandra, HBase, Vertica, Druid, Accumulo, Hypertable.
