USING STATISTICS FOR DATABASE PARTITION PRUNING ON CORRELATED COLUMNS

摘要

A system includes a database having one or more tables having multiple partitions. The database includes memory modules to store the multiple partitions, a query processor, a data manipulation language (DML) processor configured to process operations to manipulate data in one or more of the partitions and a statistics module. For each partition, the statistics module maintains a partition profile and stores the partition profile in a statistics cache. The partition profile includes at least a first interval of data range values per column for one or more columns. The statistics module updates at least the first interval of a partition profile for a partition with new data range values responsive to the DML processor processing an operation to manipulate data in the partition. The database includes a partition pruning module that is configured to include partitions responsive to a received query based on the partition profile.

主权项

1. A system for pruning one or more partitions of a table having multiple partitions using statistics of the partitions, the system comprising:
a database comprising one or more tables having multiple partitions, wherein a partition scheme of the partitions is based on a value range of a first column in each of the partitions, the database further comprising:
memory modules storing one or more of the multiple partitions of the tables;a query processor configured to receive a query;a data manipulation language (DML) processor configured to process operations to manipulate data in one or more of the partitions;a statistics module that is operably coupled to the DML processor and to a statistics cache, wherein for each partition the statistics module maintains a partition profile and stores the partition profile in the statistics cache, the partition profile having at least a first interval of data range values per column for one or more columns, wherein the statistics module is configured to update at least the first interval of a partition profile for a partition with new data range values responsive to the DML processor processing an operation to manipulate data in the partition; anda partition pruning module that is operably coupled to the query processor, the DML processor and the statistics module, wherein the partition pruning module is configured to include partitions responsive to a received query based on the partition profile.