MOD in SQL is the operator that calculates the remainder. Usage: MOD(x, y), where x is the dividend and y is the divisor. Returns the remainder after dividing x by y, which is always a nonnegative number. Use cases include calculating the day of the week, checking parity, and detecting whether a number is a multiple.
#What does MOD mean in SQL?
MOD is an operator in SQL that is used to calculate the remainder between two numbers.
Usage:
<code>MOD(x, y)</code>
Where:
- x is the dividend
- y is the divisor
Return value:
Returns the remainder after dividing x by y.
Example:
<code>SELECT MOD(10, 3); -- 返回 1 SELECT MOD(15, 4); -- 返回 3</code>
Note:
- ##If y is 0, MOD will return NULL.
- The result of MOD is the same as the remainder of division, but the result of MOD is always non-negative.
Application scenarios:
MOD operator is usually used in the following scenarios:- Calculate the day of the week:
- MOD (DATE('now'), 7)
Returns the day of the week the current date is (0 is Sunday, 1 is Monday, and so on).
Check parity: - MOD(x, 2)
Returns 0 if x is an even number and 1 if x is an odd number.
Check whether it is a multiple of a certain number: - MOD(x, y) = 0
means x is a multiple of y.
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