Syntax
round_number::=
Purpose
ROUND
returns n
rounded to integer
places to the right of the decimal point. If you omit integer
, then n
is rounded to zero places. If integer
is negative, then n
is rounded off to the left of the decimal point.
n
can be any numeric data type or any nonnumeric data type that can be implicitly converted to a numeric data type. If you omit integer
, then the function returns the value ROUND
(n, 0) in the same data type as the numeric data type of n
. If you include integer
, then the function returns NUMBER
.
ROUND
is implemented using the following rules:
If n
is 0, then ROUND
always returns 0 regardless of integer
.
If n
is negative, then ROUND
(n, integer) returns -ROUND
(-n, integer).
If n
is positive, then
ROUND(n, integer) = FLOOR(n * POWER(10, integer) + 0.5) * POWER(10, -integer)
ROUND
applied to a NUMBER
value may give a slightly different result from ROUND
applied to the same value expressed in floating-point. The different results arise from differences in internal representations of NUMBER
and floating point values. The difference will be 1 in the rounded digit if a difference occurs.
See Also:
Table 2-8 for more information on implicit conversion
"Floating-Point Numbers" for more information on how Oracle Database handles BINARY_FLOAT
and BINARY_DOUBLE
values
FLOOR and CEIL, TRUNC (number) and MOD for information on functions that perform related operations
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