By default, a PolarDB for MySQL cluster contains one primary node and one read-only node. When you add a read-only node, you can select to add a read-only row store node or a read-only column store node. This topic describes how to add a read-only column store node.
Precautions
The in-memory column index feature cannot be enabled along with the failover with hot standby feature. If a cluster contains a read-only node where the failover with hot standby feature is enabled, you cannot add read-only column store nodes to the cluster.
Procedure
Result

In the preceding figure, Read-only Columnar Node is the new column store node and Read-only is the original row store node.