To gain access to the change data that is associated with a capture instance, the user must be granted select access to all the captured columns of the associated source table. In addition, if a gating role is specified when the capture instance is created, the caller must also be a member of the specified gating role. Other general change data capture functions for accessing metadata will be accessible to all database users through the public role, although access to the returned metadata will also typically be gated by using select access to the underlying source tables, and by membership in any defined gating roles.

**DDL Operations to Change Data Capture Enabled Source Tables**

All base column types are supported by change data capture. The following table lists the behavior and limitations for several column types.