This topic contains examples of using proximity operators with nested subexpressions.
Using the two proximity operators as sub-expressions to the other Boolean operators is supported. For example, the expression:
(chardonnay NEAR/5 California) AND Sonoma
is a valid expression because
NEAR
is being used as a sub-expression to the
AND
operator.
However, you cannot use the non-proximity operators
(AND
,
OR
,
NOT
) as sub-expressions to the
NEAR
and
ONEAR
operators.
For example, the expression:
(chardonnay OR merlot) NEAR/5 California
is not a valid expression.
This invalid expression, however, could be specified as:
(chardonnay NEAR/5 California) OR (merlot NEAR/5 California)
The proximity operators are therefore leaf operators. That is, they accept only words and phrases as sub-expressions, but not the other Boolean operators.
Using proximity operators with the key restrict operator also has the same limitations when used as sub-expressions.
For example, the query:
("car maker" : aston) NEAR/3 martin
is not valid.
However, the following format for a key restrict operator is acceptable:
"car maker" : (aston NEAR/3 martin)
For other support limitations, see the topic about interaction of Boolean search with other features.