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Spelling Error Tolerant Substring Implementation Details

Adds Spelling-error tolerance to 'subString' search.  This makes use of the double metaphone indexed value as well as literal property values. 


The Spelling Error Tolerant Substring search has the following characteristics:

  • This search is case in-sensitive. 
  • It searches on the double metaphone property value and literal property value.  
  •  The  literal property part (without the wild cards) of the query is boosted by .5.  This gives a literal match priority.  
  • Parsing is done with the following analyzers:

    • dm_propertyValue - Uses our custom double metaphone analyzer.  This has the following filters:

      • LowerCaseFilter - for setting to lowercase
      • StopFilter - to remove stop words (the, a, etc.) from the search
      • DoubleMetaphoneFilter - for testing double metaphone sounds
    • literal_propertyValue - Uses our custom literal analyzer.  This literal analyzer uses Lucene's WhitespaceTokenizer with Lucene's LowerCaseFilter.


Example of use:

The following examples are based on the Automobiles coding scheme.

Example 1:

Search string: car

Lucene query: dm_propertyValue:"KR" literal_propertyValue:"car"^0.5

Result: 2 results

  • Result 1
    • entity code: C0001
    • entity description: Car
  • Result 2
    • entity code: C0002
    • entity description: Kar

Example 2:
Search string: General Motors

Lucene query: dm_propertyValue:"JNRL KNRL MTRS" literal_propertyValue:"general motors"^0.5

Result: 1 result

  • entity code: GM
  • entity description: General Motors

Associated JUnits:

Junits can be found here:



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