Are you asking about what changes you need to make on the app server after making the schema name changes on the databases? In WebSphere you would need to update the namespace bindings for the PegaRULES and PegaDATA defaultSchemas.
Also be sure that when you did the rename at the database level you updated the stored procedures, functions, triggers, etc. Most database tools will only rename the signature line and not the references within the body. For example, it would rename the stored procedure DATA.sppr_sys_statusnodes_set to APP_DAA.sppr_sys_statusnodes_set but it would not correct the references within the stored procedure to the DATA.pr_sys_statusnodes table to APP_DATA.pr_sys_statusnodes.
Just need one more clarification, are the name space binding values to default pega schemas would be enough to refer the new schemas? or do we need to make any additional changes at the Websphere level or any local files?