SYSTEMS AND METHODS FOR PERFORMING A NESTED JOIN OPERATION

摘要

Systems and methods are provided for performing a nested join operation. Partitioning key values are computed for an outer data source using a partitioning key function used to partition an inner table. A join process is established for each of a plurality of partitions of the inner table (at 204), with a given partition of the inner table representing a plurality of partitioning key values. Each row from the outer data source is routed to a join process according to its associated partitioning key value (at 206). The inner table is probed to return a row from the inner table having the partitioning key value associated with the row from the outer data source (at 208). The row from the outer data source and the row returned from the inner table are joined to form a row in a combined table (at 210).