Methods and apparatus, including computer program products, are provided for a distributed database application system. In some implementations, there may be provided a method which may include receiving, by a transaction controller defining a data access layer of a database and via an application server associated with a client interface, a request to modify data stored in the database, the transaction controller comprising an application programming interface (API); establishing, by the API, a virtual connection between the transaction controller and the application server, and a physical connection between the transaction controller and the database; providing, by the API to the application sever via the virtual connection in response to the request, a representation of the data; and executing, by the application server, the request, the executing comprising modifying, via the virtual connection, the representation of the data without modifying the data stored in the database. Related systems, methods, and articles of manufacture are also disclosed.