11. A computer program product having program codes stored on a computer-usable medium for searching for all occurrences of a queried date in a plurality of electronic documents, the method comprising: a program code for processing each of the electronic documents via extended regular expression matching to generate a canonicalized format of each occurrence of any date in any date format in the document; a program code for packaging the canonicalized format of each occurrence to support one or more types of date querying; a program code for reconstructing a span and location of one of the occurrences of the queried date after removal of html tags from crawled html content of one of the electronic documents; and a program code for outputting all occurrences of the queried date using the packaged canonicalized format.
11. A computer program product having program codes stored on a computer-usable medium for searching for all occurrences of a queried date in a plurality of electronic documents, the method comprising: a program code for processing each of the electronic documents via extended regular expression matching to generate a canonicalized format of each occurrence of any date in any date format in the document; a program code for packaging the canonicalized format of each occurrence to support one or more types of date querying; a program code for reconstructing a span and location of one of the occurrences of the queried date after removal of html tags from crawled html content of one of the electronic documents; and a program code for outputting all occurrences of the queried date using the packaged canonicalized format. 12. The computer program product of claim 11 further comprising: a program code for scanning the document for all occurrences of all date in any date format in the document; a program code for disambiguating the format of each of the occurrences; and a program code for creating the canonicalized format for each of the disambiguated occurrences.