A comprehensive analysis of the exception handling mechanism of Oracle Developer

Oracle developer is well known for its rapid data processing development, and its exception handling mechanism is also relatively perfect, not to be underestimated.

1, the advantages of the exception

If there are no exceptions, in the program, you should check the success or failure of each command, as

BEGIN
SELECT ...
-- check for ’no data found’ error
SELECT ...
-- check for ’no data found’ error
SELECT ...
-- check for ’no data found’ error

The disadvantage of this approach is that error handling is not separated from normal processing, the readability is poor, the use of exceptions makes it easy to handle errors, and exception handlers are separated from normal transaction logic to improve readability, such as

BEGIN
SELECT ...
SELECT ...
SELECT ...
...
EXCEPTION
WHEN NO_DATA_FOUND THEN -- catches all ’no data found’ errors