ABS (x)[Function] returns the absolute value of x. [parameter] x, number expression. [Return] number. [Example] select abs (100), abs (-100) from dual;
Sign (x)[Function] returns the positive and negative values of x. [parameter] x, number expression [Return] number. If the return value is positive, 1 is returned. If the return value is negative,-100 is returned. [Example] select sign ), sign (-100), sign (0) from dual;
Ceil (x)[Function] returns the smallest integer value greater than or equal to x [parameter] x, numeric expression [Return] Number [Example] select ceil (3.1), ceil (2.8 + 1.3 ), ceil (0) from dual; returns 4, 5, 0
Floor (x)[Function] returns the maximum integer less than or equal to x [parameter] x, numeric expression [Return] Number [Example] select floor (3.1), floor (2.8 + 1.3 ), floor (0) from dual; returns 4, 5, 0
Power (x, y)[Function] returns the y power of x. [parameter] x, y numeric expression. [Return] number. [Example] select power (2.5, 2), power (1.5, 0 ), power (20,-1) from dual; returns: 6.25, 1, 0.05 [close] exp (y) returns the power y of e. (E is a mathematical constant) [relational] z = power (x, y), then y = 1/log (z, x) (condition z, x> 0)
Exp (y)[Function] returns the y Power of e (e is a mathematical constant) [parameter] y, numeric expression [Return] Number [Example] select exp (3), exp (0 ), exp (-3) from dual; returns: 20.0855369, 1, 0.049787068 [close] power (x, y) returns the power y of e. [Opposite] ln (y) returns the Base natural logarithm of e.
Log (x, y)[Function] returns the base-x logarithm of y. [parameter] x, y, numeric expression, [condition] x, y must be greater than 0 [Return] Number [Example] select power (0.25), log (), 1/log () from dual; Return: 16, 2 select power (6.5, 3), log (274.625, 3), 1/log (power (6.5, 3), 6.5) from dual; Return: 274.625, 0.195642521, 3 [close] ln (y) returns the base y logarithm of e. (E is a mathematical constant) [relational] z = power (x, y), then y = 1/log (z, x) (condition z, x> 0)
Ln (y)[Function] returns the logarithm of y Based on e (e is a mathematical constant). [parameter] y, numeric expression (condition y> 0) return number [Example] select exp (3), exp (-3), ln (20.0855369), ln (0.049787068) from dual; Return: 20.0855369, 0.049787068, 3, -3 [close] log (x, y) returns the logarithm of y based on x. [opposite] exp (y) returns the y Power of e.
Mod (x, y)[Function] returns the remainder of x divided by y. [parameter] x, y, numeric expression [Return] Number [Example] select mod (), mod () from dual; return: 7, 0
Round (x [, y])Function: returns the rounded value. [parameter] x, y, numeric expression. If y is not an integer, the integer y is truncated. If y is greater than 0, the rounded value is y, if y is less than 0, it is rounded to the y place to the left of the decimal point. Return number [Example] select round (5555.6666, 2.1), round (5555.6666,-2.6), round (5555.6666) from dual; Return: 5555.67, 5600,555 6 [close] trunc (x [, y]) returns the truncated value, which is used in the same way as round (x [, y]), but is not rounded down.
Trunc (x [, y])[Function] returns the x, y, numeric expression after x is truncated by precision y. If y is not an integer, the y integer is truncated, if y> 0, it is truncated to y decimal places. If y is smaller than 0, it is truncated to y decimal places on the left. Other data before decimal places is represented by 0. Return number [Example] select trunc (5555.66666, 2.1), trunc (5555.66666,-2.6), trunc (5555.033333) from dual; return: 5555.66 5500 5555 [close] round (x [, y]) returns the truncated value. The usage is the same as that of trunc (x [, y]), but only rounding
Sqrt (x)[Function] returns the square root of x. [parameter] x number expression. [Return] number. [Example] select sqrt (64), sqrt (10) from dual. Return: 8, 3.16227766.