24. An apparatus comprising: hardware means for receiving a query instruction; hardware means for determining, in response to receiving the first query instruction, a compression ratio of a first compression value for a query result decision diagram and a second compression value for a compressed query result set, the first compression value being indicative of a data size of the query result decision diagram and the second compression value being indicative of the data size of the compressed query result set; hardware means for comparing the compression ratio to a threshold ratio; and hardware means for causing transmission of the query result decision diagram or causing transmission of the compressed query result set based upon a result of the comparison of the compression ratio to the threshold ratio.
25. An apparatus according to claim 24 further comprising: hardware means for generating a dictionary associated with the query result decision diagram, the dictionary including one or more decoding keys for decoding data in the first query result decision diagram; and hardware means for transmitting the dictionary based upon the relationship between the compression ratio and the threshold ratio.