FLOOR function
Floor returns the integer below the number, regardless of whether positive or negative.
SQL> select floor(1.1) from dual;
FLOOR(1.1)
----------
1
SQL> select floor(1.9) from dual;
FLOOR(1.9)
----------
1
SQL> select floor(-1.1) from dual;
FLOOR(-1.1)
-----------
-2
SQL> select floor(-1.9) from dual;
FLOOR(-1.9)
-----------
-2
SQL> select floor(0) from dual;
FLOOR(0)
----------
0
SQL>