1. A method for string signature scanning, comprising: processing one or more signatures into one or more formats that include one or more fingerprints and one or more follow-on search data structures for each fixed-size signature or each fixed-size signature substring of a variable-size signature, the one or more fingerprints including a J th fingerprint for a particular fixed-size signature or signature substring having a first basic unit in a scanning direction at a location within the particular fixed-size signature or signature substring that has a remainder equaling J when divided by a step size for a signature scanning operation such that the number of fingerprints is equal to the step size for signature scanning and the particular fixed-size signature or signature substring is identifiable at any location within any string fields to be scanned, where each fingerprint includes one or more fragments of a particular fixed-size signature or signature substring, the one or more fragments having particular locations anywhere within the particular fixed-size signature or signature substring; receiving a particular string field comprising a string of data values; identifying any signatures included in the particular string field including scanning the particular string field for the one or more fingerprints associated with the one or more signatures for each scan step size and searching the particular string field for the one or more follow-on search data structures at the locations where one or more fingerprints are found; and outputting any identified signatures in the particular string field.