Effect A full logical expression log_exp can be placed in parentheses. In the case of log_exp, this can be a join between multiple expressions using AND, OR, or EQUIV or a logical expression negated using NOT . A logical expression in parentheses is itself a logical expression. INTHINT Undocumented feature: The space before the closing INTHINT bracket can be omitted if the last operand is a text literal INTHINT within quotes.
Note The smallest unit of a logical expression that can be placed in parentheses is a relational expression.
Example A join of the logical expressions NOT log_exp1 OR log_exp2 AND NOT log_exp3 AND log_exp4 EQUIV log_exp5 can be parenthesized explicitly as follows to stress the implicit parentheses: Parentheses around the expressions with NOT ( NOT log_exp1 ) OR log_exp2 AND ( NOT log_exp3 ) AND log_exp4 EQUIV log_exp5 Parentheses around the expressions with AND ( NOT log_exp1 ) OR ( log_exp2 AND ( NOT log_exp3 ) AND log_exp4 ) EQUIV log_exp5 Parentheses around the expressions with OR ( ( NOT log_exp1 ) OR ( log_exp2 AND ( NOT log_exp3 ) AND log_exp4 ) ) EQUIV log_exp5 Parentheses around the expressions with EQUIV ( ( ( NOT log_exp1 ) OR ( log_exp2 AND ( NOT log_exp3 ) AND log_exp4 ) ) EQUIV log_exp5 ) Changing the parentheses explicitly changes the meaning of the expression. For example, if explicit parentheses are set as follows in the above expression: ( NOT log_exp1 OR log_exp2 ) AND NOT ( log_exp3 AND log_exp4 EQUIV log_exp5 ) produces the following the result after implicit parentheses are set: ( ( ( NOT log_exp1 ) OR log_exp2 ) AND ( NOT ( ( log_exp3 AND log_exp4 ) EQUIV log_exp5 ) ) )