mysql-cursor

cursor

1. declare -> declare c1 cursor for ....(sql select salary from employees;)
2. open    -> open c1;
3. operation ->
      loop
        fetch c1 into a;
      end loop;
4. close -> close c1;

 

实例：

delimiter //
create procedure p_11()
begin
 declare c_total float(8,2);
 declare c_name varchar(20);
 declare c_salary float(8,2);
 declare c_comm float(3,2);
 declare c1 cursor for select name, salary, comm from employees;
 declare exit handler for not found
 begin  close c1; end;

 open c1;
 loop 
   fetch c1 into c_name, c_salary, c_comm;
   select ( c_salary * ifnull(c_comm,0) + c_salary ) into c_total from dual;
   update salary set salary=c_total where name=c_name;
 end loop;
 close c1;
end
//
delimiter ;

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