SQL 函数数字函数ABS在本页ABSReturns the absolute value of x.SyntaxABS(x)ExamplesSELECT ABS(-5);+---------+| ABS(-5) |+---------+| 5 |+---------+SELECT ABS(-5.5);+-----------+| ABS(-5.5) |+-----------+| 5.5 |+-----------+