Scientific journal

ISSN 1814-2400

INFORMATION SCIENCE AND CONTROL SYSTEMS

Grigor’ev Yu.A., Pluzhnikova O. Yu.

ESTIMATION OF ATTRIBUTE VALUES IN JOIN TABLES WHILE OPTIMIZING RELATIONAL DATABASE QUERY

The article analyzes the problem of estimating join tables cardinality in the process of calculating the cost of relational database query plan. A new algorithm for estimating the distinct values of attributes is proposed. The algorithm allows reducing inaccuracy in cardinality estimation. The consistency of proposed algorithm is proved.

Keywords: cost model, query optimization, distinct values of attributes, tables cardinality