Spec-Zone .ru
спецификации, руководства, описания, API
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Operator precedences are shown in the following list, from highest precedence to the lowest. Operators that are shown together on a line have the same precedence.
INTERVALBINARY, COLLATE!- (unary minus), ~ (unary bit inversion)^*, /, DIV, %, MOD-, +<<, >>&|= (comparison), <=>, >=, >, <=, <, <>, !=, IS, LIKE, REGEXP, INBETWEEN, CASE, WHEN, THEN, ELSENOT&&, ANDXOR||, OR= (assignment), :=
The precedence of =
depends on whether it is used as a comparison operator (=
) or as an assignment
operator (=
). When
used as a comparison operator, it has the same precedence as <=>
, >=
, >
, <=
, <
, <>
, !=
, IS
,
LIKE
, REGEXP
, and IN
. When used as an assignment operator, it has the same precedence as :=
. Section 13.7.4, "SET
Syntax", and Section 9.4,
"User-Defined Variables", explain how MySQL determines which interpretation of =
should apply.
The meaning of some operators depends on the SQL mode:
By default, ||
is a logical OR
operator. With PIPES_AS_CONCAT
enabled, ||
is string concatenation, with a precedence between ^
and the unary operators.
By default, !
has a higher precedence than NOT
. With HIGH_NOT_PRECEDENCE
enabled, !
and NOT
have the same precedence.
See Section 5.1.7, "Server SQL Modes".
The precedence of operators determines the order of evaluation of terms in an expression. To override this order and group terms explicitly, use parentheses. For example:
mysql>SELECT 1+2*3;
-> 7mysql>SELECT (1+2)*3;
-> 9