Operators are used in code to perform computations. This topic describes the operators that are supported by MaxCompute.

The following table describes the operator types that are supported by MaxCompute.

Operator typeDescription
Relational operatorsUsed for comparison operations.
Arithmetic operatorsUsed for arithmetic operations.
Bitwise operatorsUsed for operations on binary digits.
Logical operatorsUsed to connect multiple conditions. In most cases, logical operators are used to connect expressions or values of the BOOLEAN type.

## Relational operators

OperatorDescription
A=B
• If A or B is NULL, NULL is returned.
• If A is equal to B, TRUE is returned. Otherwise, FALSE is returned.
A<>B
• If A or B is NULL, NULL is returned.
• If A is not equal to B, TRUE is returned. Otherwise, FALSE is returned.
A<B
• If A or B is NULL, NULL is returned.
• If A is less than B, TRUE is returned. Otherwise, FALSE is returned.
A<=B
• If A or B is NULL, NULL is returned.
• If A is less than or equal to B, TRUE is returned. Otherwise, FALSE is returned.
A>B
• If A or B is NULL, NULL is returned.
• If A is greater than B, TRUE is returned. Otherwise, FALSE is returned.
A>=B
• If A or B is NULL, NULL is returned.
• If A is greater than or equal to B, TRUE is returned. Otherwise, FALSE is returned.
A IS NULLIf A is NULL, TRUE is returned. Otherwise, FALSE is returned.
A IS NOT NULLIf A is not NULL, TRUE is returned. Otherwise, FALSE is returned.
A LIKE BIf A or B is NULL, NULL is returned. If String A matches Pattern B, TRUE is returned. Otherwise, FALSE is returned.
• The percent sign (%) matches an arbitrary number of characters.
• The underscore (_) matches a single character.
• To match percent signs (%) or underscores (_), you must escape percent signs (%) or underscores (_) with single quotation marks ('). After the percent signs (%) or underscores (_) are escaped, `'%'` or `'_'` is used for the match.
``````'aaa' like 'a__'= TRUE
'aaa' like 'a%' = TRUE
'aaa' like 'aab'= FALSE
'a%b' like 'a\\%b'= TRUE
'axb' like 'a\\%b'= FALSE ``````
A RLIKE BIf String A matches String Constant B or Regular Expression B, TRUE is returned. Otherwise, FALSE is returned. If B is an empty string, an error is returned. If A or B is NULL, NULL is returned.
A IN B
• If A is included in Set B, TRUE is returned. Otherwise, FALSE is returned.
• If A is NULL, NULL is returned.
• If Set B contains NULL, NULL is returned.
• Set B must be a constant set and contain at least one element. All the elements in Set B must be of the same data type.
BETWEEN ANDThe expression is `A [NOT] BETWEEN B AND C`.
• If A, B, or C is NULL, NULL is returned.
• If A is greater than or equal to B and less than or equal to C, TRUE is returned. Otherwise, FALSE is returned.
IS [NOT] DISTINCT FROMThe expression is `A IS [NOT] DISTINCT FROM B`. For more information, see IS DISTINCT FROM and IS NOT DISTINCT FROM.
A||BThis operator is used to join strings. For example, `a||b||c` is equivalent to `CONCAT(a, b, c)`.
Common use of relational operators in statements:
``````SELECT * FROM user WHERE user_id = '0001';
SELECT * FROM user WHERE user_name <> 'maggie';
SELECT * FROM user WHERE age > '50';
SELECT * FROM user WHERE birth_day >= '1980-01-01 00:00:00';
SELECT * FROM user WHERE is_female is null;
SELECT * FROM user WHERE is_female is not null;
SELECT * FROM user WHERE user_id in (0001,0010);
SELECT * FROM user WHERE user_name like 'M%';``````

Before you perform some relational operations, you must convert the data type. Otherwise, NULL may be returned. For more information about type conversions, see Type conversions.

Values of the DOUBLE type in MaxCompute are different in precision. Due to this reason, we recommend that you do not use an equal sign (=) for comparison between two values of the DOUBLE type. You can subtract a value of the DOUBLE type from another value of the DOUBLE type, and obtain the absolute value for comparison. If the absolute value is negligible, the two values of the DOUBLE type are considered equal. Example:
``````ABS(0.9999999999 - 1.0000000000) < 0.000000001
-- 0.9999999999 and 1.0000000000 have a precision of 10 decimal digits, whereas 0.000000001 has a precision of 9 decimal digits.
-- 0.9999999999 is considered equal to 1.0000000000. ``````
Note
• ABS is a built-in function provided by MaxCompute. This function is used to obtain the absolute value of its input. For more information, see ABS.
• In most cases, a value of the DOUBLE type in MaxCompute can provide a precision of 14 decimal digits.
• If you compare a value of the STRING type with a value of the BIGINT type, the data types of the values are automatically converted into DOUBLE. The precision loss may occur during the comparison. To address this issue, you can use CAST STRING AS BIGINT to convert the STRING type into BIGINT.

## Arithmetic operators

OperatorDescription
A+BIf A or B is NULL, NULL is returned. Otherwise, the result of A plus B is returned.
A-BIf A or B is NULL, NULL is returned. Otherwise, the result of A minus B is returned.
A*BIf A or B is NULL, NULL is returned. Otherwise, the result of A multiplied by B is returned.
A/BIf A or B is NULL, NULL is returned. Otherwise, the result of A divided by B is returned.
Note If A and B are of the BIGINT type, the return value is of the DOUBLE type.
A%BIf A or B is NULL, NULL is returned. Otherwise, the remainder of A divided by B is returned.
+AA is returned.
-AIf A is NULL, NULL is returned. Otherwise, -A is returned.
A DIV BIf A or B is NULL, NULL is returned. Otherwise, the result of A DIV B is returned.
Common use of arithmetic operators in statements:
``SELECT age+10, age-10, age%10, -age, age*age, age/10, age div 10 FROM user;``
Note
• You can use only the values of the STRING, BIGINT, or DOUBLE type to perform arithmetic operations. You cannot use the values of the DATE or BOOLEAN type to perform arithmetic operations.
• Values of the STRING type are implicitly converted into the DOUBLE type before arithmetic operations.
• If you use values of the BIGINT and DOUBLE types to perform arithmetic operations, the value of the BIGINT type is implicitly converted into the DOUBLE type before the operations. The return value is of the DOUBLE type.
• If A and B are of the BIGINT type, the return value is of the DOUBLE type after you perform the A/B operation. For other arithmetic operations, the return value is of the BIGINT type.

## Bitwise operators

OperatorExampleDescription
• BITAND
• &
• `BITAND(A,B)`
• `A&B`
The bitwise AND result of A and B is returned. For example, the result of `1&2` is 0, the result of `BITAND(1,3)` is 1, and the bitwise AND result of NULL and any value is NULL. A and B must be of the BIGINT type.
• BITOR
• |
• `BITOR(A,B)`
• `A|B`
The bitwise OR result of A and B is returned. For example, the result of `1|2` is 3, the result of `BITOR(1,3)` is 3, and the bitwise OR result of NULL and any value is NULL. A and B must be of the BIGINT type.
• BITNOT
• ~
• `BITNOT(A)`
• `~A`
The bitwise NOT result of A is returned. For example, the result of `~1` is -2, the result of `BITNOT(7)` is -8, and the bitwise NOT result of NULL is NULL. A must be of the BIGINT type.
• BITXOR
• ^
• `BITXOR(A,B)`
• `A^B`
The bitwise XOR result of A and B is returned. For example, the result of `1^2` is 3, the result of `BITXOR(4,5)` is 1, and the bitwise XOR result of NULL and any value is NULL. A and B must be of the BIGINT type.
Note Bitwise operators do not support implicit type conversions. You can use only values of the BIGINT type in bitwise operations.

## Logical operators

OperatorDescription
A and BTRUE and TRUE=TRUE
TRUE and FALSE=FALSE
FALSE and TRUE=FALSE
FALSE and FALSE=FALSE
FALSE and NULL=FALSE
NULL and FALSE=FALSE
TRUE and NULL=NULL
NULL and TRUE=NULL
NULL and NULL=NULL
A or BTRUE or TRUE=TRUE
TRUE or FALSE=TRUE
FALSE or TRUE=TRUE
FALSE or FALSE=FALSE
FALSE or NULL=NULL
NULL or FALSE=NULL
TRUE or NULL=TRUE
NULL or TRUE=TRUE
NULL or NULL=NULL
NOT AIf A is NULL, NULL is returned.
If A is TRUE, FALSE is returned.
If A is FALSE, TRUE is returned.
Note Logical operators do not support implicit type conversions. You can use only the values of the BOOLEAN type in logical operations.

## Operator precedence

The following table lists the precedence of operators in descending order. If operators have the same precedence, the operations are performed from left to right by default.
OperatorPrecedence
IS (NOT) NULL1
^2
*, /, %, DIV3
+, -4
||5
&6
|7
(NOT) LIKE, (NOT) RLIKE, =, ==, IS (NOT) DISTINCT FROM, <>, ! =, <=, <, >=, >8
(NOT) IN, (NOT) BETWEEN AND9
NOT10
AND11
OR12
If you want to preferentially process some operations, you must enclose the operations in parentheses (). Example:
``````a=1 and b=1 or c=1        -- a and b are calculated before c.
a=1 and (b=1 or c=1)      -- b and c are calculated before a.        ``````