ROUND function
ROUND converts a decimal value to the next highest absolute value if the value is 0.5 or greater.
"Next highest absolute value" for negative numbers rounds to the negative value of the absolute value of the negative number; e.g., ROUND(-6.8) = -7.
SQL> select ROUND(1.1) from dual;
ROUND(1.1)
----------
1
SQL> select ROUND(1.9) from dual;
ROUND(1.9)
----------
2
SQL> select ROUND(-1.1) from dual;
ROUND(-1.1)
-----------
-1
SQL> select ROUND(-1.9) from dual;
ROUND(-1.9)
-----------
-2
SQL> select ROUND(0) from dual;
ROUND(0)
----------
0
SQL>
ROUND function may have a second argument to handle precision, which means the distance to the right of the decimal point.
The second argument defaults to 0.
SQL> select ROUND(1.99999) from dual;
ROUND(1.99999)
--------------
2
SQL> select ROUND(1.99999,0) from dual;
ROUND(1.99999,0)
----------------
2
SQL> select ROUND(1.9,1) from dual;
ROUND(1.9,1)
------------
1.9
SQL> select ROUND(1.99,2) from dual;
ROUND(1.99,2)
-------------
1.99
SQL> select ROUND(1.999,3) from dual;
ROUND(1.999,3)
--------------
1.999
SQL>
SQL>
In addition, the second argument, precision, may be negative, which means displacement to the left of the decimal point.
SQL> select ROUND(19999.99999,0) from dual;
ROUND(19999.99999,0)
--------------------
20000
SQL> select ROUND(9.9,-1) from dual;
ROUND(9.9,-1)
-------------
10
SQL> select ROUND(19.99999,-2) from dual;
ROUND(19.99999,-2)
------------------
0
SQL> select ROUND(199.99999,-3) from dual;
ROUND(199.99999,-3)
-------------------
0
SQL>
SQL>