1. A computer implemented method for performing a query on a database, wherein a numerical value subject of the query is represented as a ciphertext determined using additive homomorphic encryption, and the ciphertext is comprised of multiple parts including at least a first sub-ciphertext and a second sub-ciphertext, the method comprising: storing the first sub-ciphertext and the second sub-ciphertext in the database, wherein the first sub-ciphertext and the second sub-ciphertext are part components of the ciphertext such that decryption of the ciphertext requires at least the first sub-ciphertext and the second sub-ciphertext, the first sub-ciphertext and the second sub-ciphertext are stored in separate attributes in the database, and are each determined based on whole of the numerical value, wherein the second sub-ciphertext is determined independently of the determination of the first sub-ciphertext; generating a query involving a computation to be performed on the first sub-ciphertext and the second sub-ciphertext stored in the database; and performing the computation on the first sub-ciphertext and the second sub-ciphertext to determine an encrypted answer to the query without requiring decryption of the first sub-ciphertext and the second sub-ciphertext.