1. A string similarity assessment method, comprising: using a processor-based device; generating a first hashtable using a hash function for a first input string comprising characters from a character set; generating a second hashtable using the hash function for a second input string comprising characters from the character set, wherein, for the first hashtable and the second hashtable, the hash function assigns the characters as keys and character positions in the strings as values; determining a character similarity index for each of the first input sting and the second input string based on comparing a similarity of the values for each key in the first hashtable and the second hashtable; determining a string similarity index for transforming the first string into the second string by selecting the character similarity index for the first input sting or the second input string; determining a total disordering index representative of an alignment score of each key in the first hashtable with its respective key in the second hashtable; and determining a string similarity metric based on the string similarity index and the total disordering index.