Question

I am getting an error in the following code below. The error is #1329 – No data – zero rows fetched, selected, or processed. What exactly does this mean and what is it that i am doing incorrectly?
Thanks

create procedure cursorproc(OUT p_out DECIMAL(10,2)) begin

   declare l_salary, l_total DECIMAL(10,2);

   declare cur_1 cursor for select line_distance from elements;
       open cur_1;

   set l_total = 0;

   loop

      fetch cur_1 into l_salary;

         set l_total = l_total + l_salary;
         end loop;

   close cur_1;

   set p_out = l_total;

end;

Answer 1

You should a DECLARE HANDLER for the cursor when no more data is found: in docs you can find about how to do so.

Use

DECLARE handler_type HANDLER FOR condition_value[,...] sp_statement

Where handler type is one of: CONTINUE, EXIT or UNDO

Condition value is one of SQLSTATE [VALUE] sqlstate_value | condition_name | SQLWARNING | NOT FOUND | SQLEXCEPTION | mysql_error_code. In this case NOT FOUND is what you’re (maybe) looking for.

So your code would become something like this:

CREATE PROCEDURE cursorproc(OUT p_out DECIMAL(10,2)) 
BEGIN
   DECLARE l_salary, l_total DECIMAL(10,2);
   DECLARE _continue INT DEFAULT 0;

   DECLARE cur_1 CURSOR FOR SELECT line_distance FROM elements;   
   DECLARE CONTINUE HANDLER FOR NOT FOUND
    SET _continue =1;
   OPEN cur_1;
   SET l_total = 0;
   REPEAT
      FETCH cur_1 INTO l_salary;
      SET l_total = l_total + l_salary;
      UNTIL _continue = 1;
   END REPEAT;
   CLOSE cur_1;
   SET p_out = l_total;
END;

Also review the docs for further information.