Patent ID: 8793287
Filing Date: 2014-07-29
Classification: G06F

Abstract:
1. A method in a computer system comprising operating the computer system to perform steps for a join operation between a first data table and a second data table based on a first attribute of the first data table and a second attribute of the second data table, the steps including: receiving a plurality of reduction data sets corresponding to a plurality of first partitions, wherein the first data table comprises the plurality of first partitions, wherein the plurality of first partitions are distributed among a first plurality of servers, each reduction data set comprising value IDs representative of actual values of the first attribute in the corresponding first partition; and associating each value ID among the plurality of reduction data sets with a unique global ID, wherein the second data table comprises a plurality of second partitions distributed among a second plurality of servers, wherein for at least one of the second partitions: generating a mapping including, for each value ID among the plurality of reduction data sets, forming a data pair comprising the value ID paired with its associated global ID when the actual value represented by the value ID occurs among actual values comprising the second attribute of the second partition; and generating a globalized list comprising data pairs of a document ID from the second partition paired with a global ID from the mapping, the document ID identifying a data record in the second partition in which the actual value of its second attribute is represented by the value ID that is paired with the global ID, wherein a plurality of first globalized lists from one or more of the first partitions are combined into a first compiled list, wherein a plurality of second globalized lists from one or more of the second partitions are combined into a second compiled list, wherein the first and second compiled lists are joined based on global IDs in the first compiled list and the global IDs in the second compiled list.