On-the-fly encoding method for efficient grouping and aggregation

摘要

Embodiments include a method and computer program product for encoding data while it is being processed as part of a query is provided. The method includes receiving a query request and determining a set of values associated with data to be encoded for completing the query request. The method also includes encoding those values such that any subsequent processing operations can be performed on the encoded values to complete the requested query. After performing the subsequent processing operations to complete the requested query, each value is decoded back to its original value.

主权项

1. A method for encoding data while being processed as part of a query, the method comprising:
receiving the query; determining a first set of values for completing the query, the first set of values being associated with the data; reducing the first set of values, wherein reducing the first set of values comprises:
computing an expression;correlating a first un-encoded value in the first set of values to a second un-encoded value in the first set of values based at least in part on the expression; andexcluding the first un-encoded value from the first set of values to obtain the second set of values; determining, during run-time, that the query includes a query predicate; evaluating, during run-time, the query predicate to determine that the query predicate excludes a third un-encoded value in the second set of values and does not exclude the second un-encoded value in the second set of values; encoding, during run-time and subsequent to evaluating the query predicate, the second un-encoded value to obtain an encoded value; completing the query at least in part by performing, during run-time, at least one processing operation on the encoded value; decoding the encoded value to obtain the second un-encoded value upon completion of the query.