Columnar or column-oriented databases are based on columns. Data in a certain column in a two-dimensional relation is stored together.
Unlike relational databases, adding columns is inexpensive and is done on a row-by-row basis. Rows can have a different set of columns. Tables can benefit from this structure by eliminating the storage cost of the null values. This model is best suited for distributed databases.
HBase is one of the most famous columnar databases. It is based on the Google Bigtable storage system. Column-oriented databases are designed for huge data scenarios, so they scale up easily. For small datasets, HBase is not a suitable architecture. First, the recommended hardware topology for HBase is a five-node or server deployment. Also, it needs a lot of administration and is difficult to master and learn.