Apache Solr Reference Guide Covering Apache Solr 6.0

In: "jump jumping jumped"
Tokenizer to Filter: "jump", "jumping", "jumped"
Out: "jump", "jump", "jump"
Remove Duplicates Token Filter
The filter removes duplicate tokens in the stream. Tokens are considered to be duplicates if they have the same
text and position values.
Factory class: solr.RemoveDuplicatesTokenFilterFactory
Arguments: None
Example:
One example of where RemoveDuplicatesTokenFilterFactory is in situations where a synonym file is
being used in conjuntion with a stemmer causes some synonyms to be reduced to the same stem. Consider the
following entry from a synonyms.txt file:
Television, Televisions, TV, TVs
When used in the following configuration:
In: "Watch TV"
Tokenizer to Synonym Filter: "Watch"(1) "TV"(2)
Synonym Filter to Stem Filter: "Watch"(1) "Television"(2) "Televisions"(2) "TV"(2) "TVs"(2)
Stem Filter to Remove Dups Filter: "Watch"(1) "Television"(2) "Television"(2) "TV"(2) "TV"(2)
Out: "Watch"(1) "Television"(2) "TV"(2)
Reversed Wildcard Filter
This filter reverses tokens to provide faster leading wildcard and prefix queries. Tokens without wildcards are not
reversed.
Factory class: solr.ReversedWildcardFilterFactory
Arguments:
withOriginal (boolean) If true, the filter produces both original and reversed tokens at the same positions. If
false, produces only reversed tokens.
maxPosAsterisk (integer, default = 2) The maximum position of the asterisk wildcard ('*') that triggers the
reversal of the query term. Terms with asterisks at positions above this value are not reversed.
maxPosQuestion (integer, default = 1) The maximum position of the question mark wildcard ('?') that triggers
the reversal of query term. To reverse only pure suffix queries (queries with a single leading asterisk), set this to
Apache Solr Reference Guide 6.0
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