Query processing in data analysis

A device, comprising:

• a processing unit;
• a memory coupled to the processing unit and storing instructions thereon, the instructions, when executed by the processing unit, cause the processing unit to:
• receive a query including a plurality of query items associated with a plurality of target dimensions of a data entry;
• determine whether at least two of a plurality of data subsets are needed to cover the plurality of target dimensions, at least one of the plurality of data subsets including data entries corresponding to at least one of the plurality of target dimensions;
• in response to determining that the at least two of the plurality of data subsets are needed to cover the plurality of target dimensions, decompose the query into a plurality of subqueries, each of the plurality of subqueries having at least one of the plurality of query items, wherein decomposing the query into the plurality of subqueries comprises:
• determine correlations between respective pairs of query items among the plurality of query items, wherein determining the correlations comprises determining mutual information between the respective pairs of query items based on probabilities of presence of the plurality of query items in corresponding target dimensions;
• and
• determine associations of the plurality of target dimensions based on the plurality of target dimensions corresponding to the respective data subsets and the correlations;
• and
• determine a query result for the query by analyzing a data entry in the plurality of data subsets that is corresponding to a target dimension associated with the at least one query item in each of the plurality of subqueries.

A non-transitory computer storage medium with computer-executable instructions stored thereon, the instructions comprising:

• receiving a query including a plurality of query items associated with a plurality of target dimensions of a data entry;
• determining whether at least two of a plurality of data subsets are needed to cover the plurality of target dimensions, at least one of the plurality of data subsets including data entries corresponding to at least one of the plurality of target dimensions;
• in response to determining that the at least two of the plurality of data subsets are needed to cover the plurality of target dimensions, decomposing the query into a plurality of subqueries, each of the plurality of subqueries having at least one of the plurality of query items, wherein decomposing the query into the plurality of sub queries comprises:
• determining correlations between respective pairs of query items among the plurality of query items, wherein determining the correlations comprises determining mutual information between the respective pairs of query items based on probabilities of presence of the plurality of query items in corresponding target dimensions;
• and
• determining associations of the plurality of target dimensions based on the plurality of target dimensions corresponding to the respective data subsets and the correlations;
• and
• determining a query result for the query by analyzing a data entry in the plurality of data subsets that is corresponding to a target dimension associated with the at least one query item in each of the plurality of subqueries.