The boolean full-text search capability supports the following operators:

+  A leading plus sign indicates that this word must be present in each result that is returned. (InnoDB supports leading plus signs only.)

–   A leading minus sign indicates that this word must not be present in any of the results that are returned. (InnoDB supports leading minus signs only.)

Note: The – operator acts only to exclude results that are otherwise matched by other search terms. A boolean-mode search containing only terms preceded by – returns an empty result. It does not return “all results except those containing any of the excluded terms.”

(no operator)  By default (when neither + nor – is specified), the word is optional, but the results that contain it are rated higher. This mimics the behavior of MATCH() AGAINST() without the IN BOOLEAN MODE modifier.

()   Parentheses group words into subexpressions. Parenthesized groups can be nested.

*  The asterisk serves as the truncation (or wildcard) operator. It is appended to the word to be affected. Words match if they begin with the word preceding the * operator.

“   A phrase enclosed within double quotes (“) matches only results that contain the phrase exactly as typed. The full-text engine splits the phrase into words and searches for those words in the FULLTEXT index.

Nonword characters need not be matched exactly: Phrase searching requires only that matches contain exactly the same words in the same order. For example, “test phrase” matches “test, phrase”.

If the phrase contains no words that are in the index, the result is empty. The words might not be in the index if they do not exist in the text, are stopwords, or are shorter than the minimum length of indexed words.

Examples of Boolean Full-Text Search Strings

• • 'apple banana': Find results that contain at least one of the two words.
  • '+apple +juice': Find results that contain both words.
  • '+apple macintosh': Find results that contain the word “apple”, but rank results higher if they also contain “macintosh”.
  • '+apple -macintosh': Find results that contain the word “apple” but not “macintosh”.
  • '+apple ~macintosh': Find results that contain the word “apple”, but rate it lower if the result also contains “macintosh” (softer than '+apple -macintosh').
  • '+apple +(>turnover <strudel)': Find results  that contain the words “apple” and “turnover”, or “apple” and “strudel” (in any order), but rank “apple turnover” higher than “apple strudel”.
  • 'apple*': Find results that contain words such as “apple”, “apples”, “applesauce”, or “applet”.
  • '"some words"': Find results that contain the exact phrase “some words” (e.g., results that contain “some words of wisdom” but not “some noise words”).

Note: The ” characters that enclose the phrase are operator characters that delimit the phrase. They are not the quotation marks that enclose the search string itself.