MLPQ: A Linear Constraint Database System with Aggregate Operators
نویسندگان
چکیده
This paper describes the MLPQ constraint database system. The query language of MLPQ is SQL extended with linear arithmetic constraints. The input and output databases are Linear Constraint Databases (LCDBs). An important feature of the MLPQ system is that it can handle aggregate operators, Min, Max, Sum, Avg, etc. In MLPQ, these operators are evaluated for a series of linear programming (LP) problems. This approach provides an e cient way of evaluation of SQL queries with aggregate operators on linear constraint databases.
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