Any good program makes use of a language’s exception handling mechanisms.
There is no better way to frustrate an end-user then by having them run into an issue with your software and displaying a big ugly error message on the screen, followed by a program crash.
The following sections discuss different strategies to mitigate errors that might come up during operations.
Data errors are errors returned by the server because a certain data condition was not met.
In the end, you gain total control over runtime exceptions by writing error handlers within controllers and at least a global exception handler in
If the relational integrity of the database is involved (for example a foreign key check fails, duplicate key, and so on), this exception is raised. /usr/bin/env python import My SQLdb, sys mydb = My SQLdb.connect(host ='localhost', user = 'skipper', passwd = 'secret', db = 'fish') cur = mydb.cursor() ident = sys.argvfish = sys.argvprice = sys.argv statement = """INSERT INTO menu(id, name, price) VALUES("%s", "%s","%s")""" %(ident, fish, price)print "Data has been inserted using the following statement: \n",statement cur.execute(statement) Change the database login information as necessary.
In this article we will specifically cover: The following are the six different error types supported by My SQL for Python.
These are all caught when raising an error of the respective type, but their specification also allows for customized handling. But this leads to ambiguous error-handling and makes debugging difficult both for the programmer(s) who work on the application as well as the network and system administrators who will need to support the program once it is installed on the end user's machine.
column in the reference tables refers to a short time interval where a retry with backoff makes sense from an application perspective and without the application interfering of some sort.
If you extend the time horizon long enough all errors can be considered transient (like creating a bucket that does not exist or fix a password), but it won't be practical to wait in the application for it.