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The search supports the following operators:
'+' -
A leading plus sign indicates
that this word must be present in every row returned.
'-' -
A leading minus sign indicates
that this word must not be present in any row returned.
'(no operator)' -
By default (when neither + nor - is specified) the word is optional,
but the rows that contain it will be rated higher.
'>' '<' -
These two operators are used to change a word's contribution
to the relevance value that is assigned to a row.
The > operator increases the contribution
and the < operator decreases it.
See the example below.
'( )' -
Parentheses are used to group words into subexpressions.
Parenthesized groups can be nested.
'~' -
A leading tilde acts as a negation operator,
causing the word's contribution
to the row relevance to be negative.
It's useful for marking noise words.
A row that contains such a word will be rated
lower than others,
but will not be excluded altogether,
as it would be with the - operator.
'*' -
An asterisk is the truncation operator.
Unlike the other operators, it should be appended to the word.
'"' -
A phrase that is enclosed within double quote (`"')
characters matches only rows that contain the phrase literally, as it was typed.
The following examples demonstrate some search strings that use boolean full-text operators:
'apple banana' -
Find rows that contain at least one of the two words.
'+apple +juice' -
Find rows that contain both words.
'+apple macintosh' -
Find rows that contain the word ``apple'', but rank rows higher if they also contain ``macintosh''.
'+apple -macintosh' -
Find rows that contain the word ``apple'' but not ``macintosh''.
'+apple +(>turnover
'apple*' -
Find rows that contain words such as ``apple'', ``apples'', ``applesauce'', or ``applet''.
'"some words"' -
Find rows that contain the exact phrase ``some words'' (for example, rows that contain ``some words of wisdom'' but not ``some noise words''). Note that the `"' characters that surround the phrase are operator characters that delimit the phrase. They are not the quotes that surround the search string itself.
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