Oracle - Função Round

ROUND (number)

Syntax

round_number::=

Description of the illustration round_number.gif

Purpose

ROUND returns n rounded to integer places to the right of the decimal point. If you omit integer, then n is rounded to 0 places. The argument integer can be negative to round off digits left of the decimal point.

n can be any numeric datatype or any nonnumeric datatype that can be implicitly converted to a numeric datatype. The argument integer must be an integer. If you omit integer, then the function returns the same datatype as the numeric datatype of the argument. If you include integer, then the function returnsNUMBER.

For NUMBER values, the value n is rounded away from 0 (for example, to x+1 when x.5 is positive and to x-1 when x.5 is negative). For BINARY_FLOAT andBINARY_DOUBLE values, the function rounds to the nearest even value. Please refer to the examples that follow.

See Also:

Table 2-10, "Implicit Type Conversion Matrix" for more information on implicit conversion

Examples

The following example rounds a number to one decimal point:

SELECT ROUND(15.193,1) "Round" FROM DUAL;

     Round
----------
      15.2

The following example rounds a number one digit to the left of the decimal point:

SELECT ROUND(15.193,-1) "Round" FROM DUAL;

     Round
----------
        20 

The following examples illustrate the difference between rounding NUMBER and floating-point number values. NUMBER values are rounded up (for positive values), whereas floating-point numbers are rounded toward the nearest even value:

SELECT ROUND(1.5), ROUND(2.5) FROM DUAL;

ROUND(1.5) ROUND(2.5)
---------- ----------
         2          3

SELECT ROUND(1.5f), ROUND(2.5f) FROM DUAL;

ROUND(1.5F) ROUND(2.5F)
----------- -----------
   2.0E+000    2.0E+000