G-4370: Avoid using EXIT to stop loop processing unless you are in a basic loop.
Reason
A numeric for loop as well as a while loop and a cursor for loop have defined loop boundaries. If you are not able to exit your loop using those loop boundaries, then a basic loop is the right loop to choose.
Example (bad)
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38 | declare
i integer;
co_min_value constant simple_integer := 1;
co_max_value constant simple_integer := 10;
co_increment constant simple_integer := 1;
begin
i := co_min_value;
<<while_loop>>
while (i <= co_max_value)
loop
i := i + co_increment;
exit while_loop when i > co_max_value;
end loop while_loop;
<<basic_loop>>
loop
exit basic_loop when true;
end loop basic_loop;
<<for_loop>>
for i in co_min_value..co_max_value
loop
null;
exit for_loop when i = co_max_value;
end loop for_loop;
<<process_employees>>
for r_employee in (
select last_name
from employees
)
loop
sys.dbms_output.put_line(r_employee.last_name);
null; -- some processing
exit process_employees when true;
end loop process_employees;
end;
/
|
Example (good)
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34 | declare
i integer;
co_min_value constant simple_integer := 1;
co_max_value constant simple_integer := 10;
co_increment constant simple_integer := 1;
begin
i := co_min_value;
<<while_loop>>
while (i <= co_max_value)
loop
i := i + co_increment;
end loop while_loop;
<<basic_loop>>
loop
exit basic_loop when true;
end loop basic_loop;
<<for_loop>>
for i in co_min_value..co_max_value
loop
sys.dbms_output.put_line(i);
end loop for_loop;
<<process_employees>>
for r_employee in (
select last_name
from employees
)
loop
sys.dbms_output.put_line(r_employee.last_name); -- some processing
end loop process_employees;
end;
/
|