All stop words, for example, common words, such as a and the,
are removed from multiple word queries to increase search performance.
Stop word recognition in Japanese is based on grammatical information,
for example, Watson Explorer Content Analytics recognizes
whether the word is a noun or a verb. For the other languages, the
system uses special lists.
No stop words are removed during query processing if:
- All of the words in a query are stop words. If all the query terms
are removed during stop word processing, then the result set is empty.
To ensure that search results are returned, stop word removal is disabled
when all of the query terms are stop words. For example, if the word car is
a stop word and you search for car, then the search results
contain documents that match the word car. If you search for car
buick, the search results contain only documents that match the
word buick.
- The word in a query is preceded by the plus sign (+).
- The word is part of an exact match.
- The word is inside a phrase, for example, "I love my car".