1. Engine Group Namiruddin Ahmed Ali Kamil

2. 2 XMLApe XMLApe Research Group Involved in research on a number of projects that are related to XML and inspired by databases Engine Group Develop DBMS that ties XMLApe GUI to multiple XMLApe Data Sources Split query involving multiple sources into multiple queries on single sources Merge multiple result sets and return to XMLApe GUI

3. 3 XMLApe Architecture

4. 4 Splitting a Query <query xmlns="http://199.77.128.59:8080/query" "> http://199.77.128.59:8080/flights/flights.xsd Flight_1 http://199.77.128.59:8080/flights/flights.xsd Flight_2 http://199.77.128.59:8080/rentals/rentals.xsd CarRental_1 Flight_1 flights/flightflightFrom Detroit Flight_1 /flights/flight/flightTo Flight_2 /flights/flight/flightFrom CarRental_1 /flights/flight/rentalFrom CarRental_1 /rentals/rental/rentalTo Sub Query 1 Sub Query 2 Sub Query 3 Figure: Query Splitter. Splitting a multi-source distributed query into single-source query documents.

5. 5 Resulting Queries Figure: Query Splitter. Splitting a multi-source distributed query into single-source query documents. http://199.77.128.59:8080/flights/flights.xsd Flight_1 Flight_1 /flights/flight/flightFrom Detroit Sub Query 1 http://199.77.128.59:8080/query http://199.77.128.59:8080/flights/flights.xsd Flight_2 Sub Query 2 http://199.77.128.59:8080/rentals/rentals.xsd CarRental_1 CarRental_1 /rentals/rental/rentalFrom CarRental_1 /rentals/rental/rentalTo Sub Query 3

6. 6 Future Work Unify sub queries on the same data source Merge sub queries using operations like self-joins to be performed natively on data source Projections and non-equi joins Change Schema Melder to publish result schema for the user interface depending on the projections in the query document Support result reorganization Making engine page from disk Reduce memory drain when dealing with larger result sets