23. An apparatus according to claim 16 , wherein the apparatus is further directed to: receive a second query instruction; and generate a second query result decision diagram based on the second query instruction and the first query result decision diagram.
16. An apparatus comprising at least one processor and at least one memory including computer program code, the at least one memory and the computer program code configured to, with the at least one processor, direct the apparatus at least to: receive a first query instruction; determine, in response to receiving the first query instruction, a compression ratio of a first compression value for a first 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 first query result decision diagram and the second compression value being indicative of the data size of the compressed query result set; compare the compression ratio to a threshold ratio; and cause transmission of the first 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.