Systems and methods for the encoding of data in a dataset, comprising the storage of the data in an i-th temporary code list (TCL(i)); generating an i-th folder (folder(i)) from the i-th temporary code list (TCL(i)) by replacing each value by an index that refers to the same value in a reference database; generating new temporary codes, using a predetermined formula F that always combines at least two values from the i-th folder (folder(i)), and placing thereof in an (i+1)-th temporary code list (TCL(i+1)); and the recursive repetition of actions b) and c) for subsequent values of i, so long as the (i+1)-th temporary code list (TCL(i+1)) or the (i+1)-th folder (Folder(i+1)) contains one or more values more than once.