[keycloak-user] Readonly database connection

I'm currently setting up a failover scenario with a postgresql master/slave (hot-standby) database. Using the database "failover" features of wildfly in the datasource I can accomplish to failover to the second, readonly database. Now I know that certain functions won't be available when the db is readonly. Do we have any documentation about use cases that won't work on readonly dbs? Or should I just handle the whole scenario manually? Kind regards, Gunnar