Diif between Stored procedure and function

Question

HI
I want all the differences between Stored procedure and function.
Even the basic diff is Procedure does not return any value and Function must be...
Thansk In advance...

Answer 1

1) Functions are used for computations where as procedures can be used for performing business logic That's an opinion on usage not an actual difference.
3) You can have DML(insert,update, delete) statements in a function. But, you can not call such a function in a SQL query.Not true. As User defind functons limitations we can use a function that issues DML in a SELECT statement, if it uses the PRAGMA AUTONOMOUS_TRANSACTION.
4) Function parameters are always IN, no OUT is possibleEasily refutable...
SQL> CREATE OR REPLACE FUNCTION my_f (p OUT NUMBER) RETURN DATE
  2  AS
  3  BEGIN
  4     p := to_number(to_char(sysdate, 'DD'));
  5     RETURN sysdate;
  6  END;
  7  /
Function created.
SQL> var x number
SQL> var d varchar2(18)
SQL> exec :d := my_f(:x)
PL/SQL procedure successfully completed.
SQL> print d
D
18-NOV-05
SQL> print x
         X
        18
SQL>
Stored Procedure :supports deffered name resoultion Example while writing a stored procedure that uses table named tabl1 and tabl2
etc..but actually not exists in database is allowed only in during creationNot sure what this one is about...
SQL> CREATE PROCEDURE my_p AS
  2      n NUMBER;
  3  BEGIN
  4     SELECT count(*) INTO n
  5     FROM tab1;
  6  END;
  7  /
Warning: Procedure created with compilation errors.
SQL> sho err
Errors for PROCEDURE MY_P:
LINE/COL ERROR
4/4      PL/SQL: SQL Statement ignored
5/9      PL/SQL: ORA-00942: table or view does not exist
SQL>
7) A procedure may modifiy an object where a function can only return a value.An ounce of test is worth sixteen tons of assertion...
SQL> CREATE OR REPLACE FUNCTION my_f2 RETURN VARCHAR2
  2  AS
  3  BEGIN
  4       EXECUTE IMMEDIATE 'CREATE TABLE what_ever (col1 number)';
  5      RETURN 'OK!';
  6  END;
  7  /
Function created.
SQL> exec :d :=  my_f2
PL/SQL procedure successfully completed.
SQL> desc what_ever
Name                                      Null?    Type
COL1                                               NUMBER
SQL> I think there are only two differences between a procedure and a function.
(1) A function must return a value
(2) because of (1) we can use functions in SQL statements.
There are some minor difference in allowable syntax but they are to do withj RETURN values.
Cheers, APC