CQL DML: UPDATE statement

In this lesson, we will focus on the Data Manipulation Language (DML) UPDATE operations supported by Apache Cassandra.

The UPDATE statement

The UPDATE statement is used to write data in one or more columns of a given row. To identify the row for updation, values for all primary key columns for the table must be specified in the WHERE clause. Values of primary key columns cannot be updated. Values for one or more non-primary key columns are assigned using the SET keyword. If the row is non-existent, it is created. Otherwise, it is updated with the data provided. It cannot be known if the UPDATE statement resulted in an insert or an update.