round, dround
Description
Rounds a number to a specified number of digits.
- If
n
is not specified,x
is rounded to the nearest integer. - If
n
is specified,x
is rounded ton
decimal places. Ifn
is negative,x
is rounded to the left of the decimal point. If overflow occurs, an error is returned.
Syntax
ROUND(x [,n]);
Parameters
x
: the number to be rounded. It supports the DOUBLE and DECIMAL128 data types.
n
: the number of decimal places to round the number to. It supports the INT data type. This parameter is optional.
Return value
-
If only
x
is specified, the return value is of the following data type:["DECIMAL128"] -> "DECIMAL128"
["DOUBLE"] -> "BIGINT"
-
If both
x
andn
are specified, the return value is of the following data type:["DECIMAL128", "INT"] -> "DECIMAL128"
["DOUBLE", "INT"] -> "DOUBLE"
Examples
mysql> select round(3.14);
+-------------+
| round(3.14) |
+-------------+
| 3 |
+-------------+
mysql> select round(3.14,1);
+----------------+
| round(3.14, 1) |
+----------------+
| 3.1 |
+----------------+
mysql> select round(13.14,-1);
+------------------+
| round(13.14, -1) |
+------------------+
| 10 |
+------------------+
mysql> select round(122.14,-1);
+-------------------+
| round(122.14, -1) |
+-------------------+
| 120 |
+-------------------+
mysql> select round(122.14,-2);
+-------------------+
| round(122.14, -2) |
+-------------------+
| 100 |
+-------------------+
mysql> select round(122.14,-3);
+-------------------+
| round(122.14, -3) |
+-------------------+
| 0 |
+-------------------+