Change database without using export keycloak

I need to connect keycloak to another database. I done the backup of old whole db and I restored it in the new db (I didn’t use the keycloak export command because database is very large and it takes very time to do the export). I changed the standalone.xml file in datasource section but when i restart the server I receive several errors. What is the correct procedure for to do this?
Thanks at all!