A method includes generating a defined access clean room in a provider database account, as well as installing, in a consumer account, an application instance that implements the defined access clean room. The method also includes sharing, by the provider database account, source provider data with the defined access clean room, where the sharing makes the source provider data accessible to the consumer database account via the application instance. The method further includes sharing, by the provider database account, a query template with the consumer database account via the application instance. Additionally, the method includes receiving a query generated by the consumer database account based on the query template, validating that the query is consistent with the query template, responsively generating query results by executing the query, as well as storing the query results in the consumer database account.