A method and system for cross-data source query dynamic optimization

Abstract

The application discloses a kind of cross data source query dynamic optimization method and system, the method includes: in the query log retrieval SQL sentence in key word join, further identify and handle the join query sentence identified, generate the training set according to join condition and predicate information extracted from the join query sentence;Using the training set, the model is trained, and the predicate selectivity estimation model is obtained, and the predicate selectivity estimation is carried out for the given data table and predicate information;After receiving new query sentence, it is judged whether the new query sentence is cross-source join query statement, parse and extract the data table and predicate information of the new query statement, and input to the predicate selectivity estimation model to obtain the selectivity estimation parameter of all data tables;According to the selectivity estimation parameter, the data table corresponding to the new query statement is connected and sorted, and the optimal connection order is obtained, which greatly improves the query efficiency of cross data source join query.

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