A method for providing encrypted data in a database includes randomly encoding stored information. Each information part having a same part index number is added to a group having the same part index number. A number of secret keys and a tree having a number of nodes are computed. The number of nodes is the same as the number of computed secret keys and vertices between the nodes, such that for each node: one of the computed secret keys is assigned to the node; a tuple of ciphertexts is generated; and a vertex from the node is assigned to a sibling indexed with the part index number with the information part corresponding to the index number of the node. A master secret comprising all computed secret keys is computed, and the encrypted data is provided in form of a database with tuples comprising the ciphertexts and the groups.