Number function
1. ABS(x) returns the absolute value of x
SELECT ABS(-1); ---- 返回1
2.AVG(expression) Returns the average of an expression, expression is a field
SELECT AVG(age) FROM student;
3, CEIL(x)/CEILING(x ) Returns the smallest integer greater than or equal to x
SELECT CEIL(1.5); SELECT CEILING(1.5); ---- 返回2
4, FLOOR(x) Returns the largest integer less than or equal to x
SELECT FLOOR(1.5); ---- 返回1
5 , EXP(x) returns e raised to the power of ##7. LEAST(expr1, expr2, expr3, …) returns the minimum value in the list
SELECT EXP(3); ---- 计算 e 的三次方,返回20.0855369231888. LN returns the natural logarithm of the number
SELECT GREATEST(3, 12, 34, 8, 25); ---- 返回以下数字列表中的最大值349. LOG(x) returns the natural logarithm (logarithm with base e)
SELECT LEAST(3, 12, 34, 8, 25); ---- 返回以下数字列表中的最小值310. MAX(expression) returns the field expression The maximum value
SELECT LN(2); ---- 返回 2 的自然对数:0.693147180559945311, MIN(expression) returns the maximum value in the field expression
SELECT LOG(20.085536923188); ---- 返回 312, POW(x,y) /POWER(x,y) returns x raised to the power of y
SELECT MAX(age) AS maxAge FROM Student; ---- age最大值13. RAND() returns a random number from 0 to 1
SELECT MIN(age) AS minAge FROM Student; ---- age最小值14. ROUND(x) returns the nearest integer to x
SELECT POW(2,3); SELECT POWER(2,3); ---- 返回2 的 3 次方:815. SIGN(x) returns the sign of x. If x is a negative number, 0, or a positive number, it returns -1, 0 and 1
SELECT RAND(); ---- 返回 0 到 1 的随机数,若()里面有数字,RAND(x),x相同时,返回值相同16. SQRT(x) returns the square root of x
SELECT ROUND(1.23456); ---- 返回 117. SUM(expression) returns the sum of the specified field
SELECT SIGN(-10); ---- 返回 -118. TRUNCATE(x,y) returns the value x retained to y digits after the decimal point (the biggest difference from ROUND is that it will not be rounded)
SELECT SQRT(25); ---- 返回5
The above is the detailed content of What are the numeric functions in MySQL?. For more information, please follow other related articles on the PHP Chinese website!

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