1. A computer-implemented method comprising: comparing, by one or more processors of a computer system, at least one data object with one or more other data objects to determine a similarity score for the compared data objects; storing, in a storage device of the computer system, a negative key mapping for the compared data objects upon determination that the similarity score associated with the compared data objects is equal to or below a dissimilarity threshold value, the negative key mapping comprising data indicating that the compared data objects are substantially different from one another; storing a positive key mapping for the compared data objects upon determination that the similarity score associated with the compared data objects is equal to or above a similarity threshold value set higher than the dissimilarity threshold value, the positive key mapping comprising data indicating that the compared data objects are substantially identical to one another, refraining from storing a key mapping for the compared data objects upon determination that the similarity score associated with the compared data objects is between the dissimilarity threshold value and the similarity threshold value; and clustering, by the one or more processors, only data objects determined to be substantially different from one another into a negatively key-mapped group using the negative key mapping.