"Init.ora" is a text file, which can be viewed using a text editor. Alternatively, we can use DBMS_UTILITY, a PL/SQL package that comes along with the standard database installation. The DBMS_UTILITY contains many useful functions, including GET_PARAMETER_VALUE. The GET_PARAMETER_VALUE procedure gets "init.ora" parameter values. The parameter name is supplied as an input to the procedure.

DBMS_UTILITY.GET_PARAMETER_VALUE (
   parnam IN     VARCHAR2,
   intval IN OUT BINARY_INTEGER,
   strval IN OUT VARCHAR2)
  RETURN BINARY_INTEGER;

Where:

Return value is:

Here is a sample SQL *PLUS script that uses GET_PARAMETER_VALUE:

SET SEVEROUTPUT ON
DECLARE
  parnam VARCHAR2(256);
  intval BINARY_INTEGER;
  strval VARCHAR2(256);
  partyp BINARY_INTEGER;
BEGIN
  partyp := dbms_utility.get_parameter_value
			('db_files',intval, strval);

  -- check for parameter type
  IF partyp = 1 THEN
    dbms_output.put_line('The parameter type is string');
  ELSE
    dbms_output.put_line(' The parameter type is integer');
  END IF;

  -- print value	
  dbms_output.put('The parameter value is: ');
  IF partyp = 1 THEN
    dbms_output.put_line(strval);
  ELSE
    dbms_output.put_line(intval);
  END IF;

  -- if paramter type is string Print Value length
  IF partyp = 1 THEN
    dbms_output.put('Length of the string is: ');
    dbms_output.put_line(intval);
  END IF;
END;
/
show errors;
SET SEVEROUTPUT OFF

SQL>  @c:\ajay\du.sql
The parameter type is: integer
The parameter value is: 1024

PL/SQL procedure successfully completed.

No errors.
SQL>

Change the parameter type in the above example to 'db_name' and the output will be as shown below;

SQL>  @c:\ajay\du.sql
The parameter type is: string
The parameter value is: mydb
Length of the string is: 4

PL/SQL procedure successfully completed.

No errors.

Summary

You can use the DBMS_UTILITY package to get values of parameters or use the Oracle provided dynamic view V$PARAMETER to get parameter values. The TYPE column of the view contains the values 1,2 and 3 for BOOLEAN, STRING and INTEGER values respectively.