Database Query Optimization Program Research And Implementation On PAR Platform

Query optimization is a fundamental problem in database query processing. Withthe progress in the information age, the amount of data information in the database isincreasing. In order to optimize database performance, improve database efficiency,Many commercial databases are invariably applied to the query optimizer,. Becausethe internal structure and function of the actual optimizer is complex, the differentsituation has different optimization mechanism. It is estimated that the ordinarycommercial database query optimizer development need at least30man-years ofdevelopment.Because of the PAR platform for database don’t has query optimizer module,which greatly affect the PAR platform database performance. Reduce the efficiencyof PAR platform query statements and PAR platform software development.I mainlystudied the advantages and disadvantages of a relational database query optimizationtechniques, compared to the range of available technologies, according to thecharacteristics of relational algebra and PAR database platform combining, raised thequery optimizer model, suitable for relational algebra based on PAR platform, in-depth discussion of the key issues for PAR query optimization. Derived throughexamples, this model can optimize the PAR platforms query statement, and play asignificant role to improve the performance of PAR platform database.This paper did the following aspects, certain aspects of innovative:1.The original relational algebra is proposed based on the relational algebra tree,suitable for PAR platform optimized design.2.According to the principle of PAR platform database to achieve the relationalalgebra equivalent transformation rules and relational algebra optimization algorithm.3.According to the APLA language generation mechanism and PAR platformscanning mechanism based to APLA syntax unit, the development of a the PARplatform for database background query optimization algorithm module.