Creating Match Key - discovery - 23.1

Spectrum Discovery Guide

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Spectrum > Discovery
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Spectrum Discovery
Spectrum Discovery Guide
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How Do I
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A match key is a non-unique key shared by like records that identify records as potential duplicates. The match key facilitates the matching process by only comparing records that contain the same match key. The Match Key feature allows you: to:

  • Publish a match key: It allows you to publish a match key to the repository for re-use at a later point in time.
  • Preview a match key: You can preview the match key with the Input Data and the Result at the bottom of the page to avoid any potential errors.


Consider the input as below:
  • First Name - Fred
  • Last Name - Mertz
  • Gender Code - M
    With the above input, if you are required to define a match key rule that generates a match key by combining data from the record shown below, the match key is MertzFredM.
    Input Field Start Position Length
    Last Name 1 5
    First Name 1 5
    Gender Code 1 1
To create a match key, perform these steps:
  1. On the Source Details page, click the Create Match Key button.
    The Match Key page is displayed.
  2. On the Match Key page, enter a unique name for your match key in the Match Key Name field.
  3. To define the rule for your match key, select Add.
    You see the Rule Options panel on the right corner of the page.
  4. In the Rule Options panel, configure these options:
    Option Description
    It returns specified fields with consonants removed.
    Double Metaphone
    It returns a code based on a phonetic representation of their characters. Double Metaphone is an improved version of the metaphone algorithm and attempts to account for the many irregularities found in different languages.
    Indexes names by sound as they are pronounced in German. It allows names with the same pronunciation to be encoded to Koeln the same representation so that they can be matched, despite minor differences in spelling. The result is always a sequence of numbers; special characters and white spaces are ignored. This option was developed to respond to the limitations of Soundex.
    It is a message-digest algorithm that produces a 128-bit hash value, which is used to check data integrity.
    It returns a Metaphone coded key of selected fields. Metaphone is an algorithm for coding words using their English pronunciation.
    Metaphone (Spanish)
    It returns a Metaphone coded key of selected fields for the Spanish language. This Metaphone algorithm codes words using their Spanish pronunciation.
    It improves upon the Metaphone and Double Metaphone algorithms with a more exact consonant and internal vowel Metaphone3 settings that allow you to produce words or names more or less closely matched to search terms on a phonetic basis. Metaphone3 increases the accuracy of phonetic encoding to 98%. This option was developed to respond to the limitations of Soundex.
    It is a phonetic code algorithm that matches an approximate pronunciation to an exact spelling and indexes words that are Nysiis pronounced similarly. It is a part of the New York State Identification and Intelligence System. For example, you are looking for someone's information in a database of people. You believe that the person's name sounds like "John Smith," but it is, in fact, spelled "Jon Smyth." If you conducted a search looking for an exact match for "John Smith," no results would be returned. However, if you index the database using the NYSIIS algorithm and search using the NYSIIS algorithm again, the correct match will be returned because both "John Smith" and "Jon Smyth" are indexed as "JAN SNATH" by the algorithm.
    It preprocesses name strings by applying more than 100 transformation rules to single characters or to sequences of several characters. Nineteen of those rules are applied only if the characters are at the beginning of the string, while 12 of the rules are applied if they are in the middle of the string, and 28 of the rules are applied if they are at the end of the string. The transformed name string is encoded into a code that is comprised by a starting letter followed by three digits (removing zeros and duplicate numbers). This option was developed to respond to the limitations of Soundex; it is more complex and, therefore, slower than Soundex.
    This algorithm determines the similarity between 2 French-language strings based on the phonetic representation of their characters. It returns a Sonnex coded key of the selected fields.
    It returns a Soundex code of selected fields. Soundex produces a fixed-length code based on the English pronunciation of a word.
    It returns a specified portion of the selected field.
    Field name Select the field to which you want to apply the selected algorithm. For example, if you select LastName, and you choose the SubString algorithm, the SubString algorithm is applied to the data in the LastName field to produce a match key.
    Start Position Select the start position within the specified field.
    Note: You can select a start position only if you choose the SubString algorithm.
    Length Select the length of characters you want to include from the starting position.
    Note: You can select a length only if you choose the SubString algorithm.
    Pre-processing options
    Remove noise character
    It removes all non-numeric and non-alpha characters such as hyphens, white space, and other special characters from an input field.
    Sort input
    It sorts all characters or terms in an input field in alphabetical order.
    • Characters: It sorts the values of the characters from an input field prior to creating a unique ID.
    • Terms: It sorts each term value from an input field prior to creating a unique ID.
    Note: You can select the sort input only if you choose the Consonant or SubString algorithm.
  5. Select OK.
    You can now save or publish the match key. For more information, see Saving and publishing the match key.