You have a primary database and a secondary database. You want Dynamic Data Masking to send requests to the primary database if the database is available. If the primary database is unavailable, you want Dynamic Data Masking to send requests to the secondary database.

You create two connection rules. The first connection rule uses the Check Database Connection matcher to determine whether a connection to the primary database exists. The rule uses the Switch to Database rule action and Stop if Matched processing action to direct the request to the primary database if the connection is available.

If the first rule does not return a match, the Dynamic Data Masking sends the request to the second connection rule. The second rule uses the Check Database Connection matcher to determine whether a connection to the secondary database exists. If the second rule returns a match, the Switch to Database rule action instructs Dynamic Data Masking to the request to the secondary database.