$c->db_schema = 'schema1,schema2';
PostgreSQL supports multiple namespaces (schemas) within a single database, allowing you to have (e.g.) two tables with the same name. This setting allows you to control the search path so that you can have the DAViCal tables in a different schema.
Note that there is no support in DAViCal for putting the tables into a non-default schema in the first place.
Available from DAViCal version: 0.9.9 and later