[asim_ishaq]

declare
  v_counter number := 1000;
begin
  for v_counter in 1 .. 10 loop
    dbms_output.put_line('In loop v_counter = ' || to_char(v_counter));
  end loop;

  dbms_output.put_line('After Loop v_counter = ' || to_char(v_counter));

end;
/

What is the value of v_counter after for loop? Let me guess its 10. The strange thing is that within for loop the value of v_counter does change from 1 to 10 but after for loop it reset to 1000. I have found another way of writing this code that works with oracle.

If we use a while loop and increment value of v_counter within loop then it actually preserve the change. look at the following code:

declare
  v_counter number := 1000;
begin
  v_counter := 0;
  
  while v_counter < 10 loop
  
    dbms_output.put_line('In loop v_counter = ' || to_char(v_counter));
    v_counter := v_counter + 1;
    
  end loop;

  dbms_output.put_line('After Loop v_counter = ' || to_char(v_counter));

end;
/

[Dormilich]

I'd hazard a guess at a scope problem. some PLs open a new scope in loops.

[asim_ishaq]

Dormilich, on 17 February 2012 - 05:17 AM, said:

I'd hazard a guess at a scope problem. some PLs open a new scope in loops.

If for loop creates a new scope then why not the while loop?

[AdamSpeight2008]

Mostly like it something to do with the scoping rules. Most Local Wins
If it behaves like a Functional Language, then those are different "variables" with the same name.