The result of the function is:
v VARCHAR( 4000 ) if the argument is VARCHAR (not exceeding  4000  bytes) or CHAR
v CLOB(1M) if the argument is CLOB or LONG VARCHAR 
v BLOB(1M) if the argument is BLOB.

Characterto Character

character-expression : An expression that returns a value that is
of the CHAR, VARCHAR, LONG VARCHAR, or CLOB data type.

integer : The length attribute of the resulting fixed-length
character string. The value must be between  0  and  254 .

If the length of the character expression is less than the
length attribute of the result, the result is padded with
blanks up to the length of the result.

If the length of the character expression is greater than
the length attribute of the result, the result is truncated.
A warning is returned (SQLSTATE  01004 ), unless the truncated
characters were all blanks, and the character expression was
not a long string (LONG VARCHAR or CLOB).