So what is an EXPECTED database error?

[ban-all-sheds]

From a couple of hours ago:

If the error was unexpected, that can only mean that there must be some which are expected.

 

[DIYnot]

There have been a few issues this evening to say the least, but things are returning to normal (hopefully!). Apologies for the issues.

 

[PaulUszak]

That's a good question. It relates to normal software development and the way procedures are coded.

For example if the database is really busy as everyone is posting their latest dribble, it might run out of connections and you get blocked. That is (ideally should be) an unlikely situation so the programmers can't really make provision other than turning an internal message such as "ORA-12516: TNS:listener could not find available handler with matching protocol stack" into the one you posted about. Or the cleaner has unplugged the server to plug in the vacuum. Those are unexpected errors.

If you tried to log in without a password, there would be a similar error but that's to be expected sometimes, and is easily captured by the developers and handled gracefully so that the forgetful user can understand it. That's an expected error.

The general programming concept is called error handling.

 

[ban-all-sheds]

an internal message such as "ORA-12516: TNS:listener could not find available handler with matching protocol stack"

Unlikely in this instance. This site is probably running on a LAMP stack. It's certainly LA?P.

If you tried to log in without a password, there would be a similar error but that's to be expected sometimes, and is easily captured by the developers and handled gracefully so that the forgetful user can understand it. That's an expected error.

No - a user trying to log on without, or with an incorrect, password does not generate an error condition.

The general programming concept is called error handling.

If an invalid condition is expected it is not an error.

 

[cjard]

So what is an EXPECTED database error?

I would expect something like

SELECT Body FROM Messages WHERE AuthorID = 3777

would give a comprehensive list of errors, possibly over 58 thousand of them..

 

[PaulUszak]

No you're right bas, it's actually called exception handling but I didn't want to confuse you with computery technobabble.

In LAMP, I think that you've got the A wrong and the M right. It presents as Nginx with PHP and XenForo only runs on MySQL. So that would be LNMP. I hate PHP - it's crap.

 

[ban-all-sheds]

Hands up anyone who has ever output a message something like "the impossible has happened" from the exception handling in their code.

Netcraft shows it as Apache back in November last year - I didn't refresh.

[clutch]Maybe it's LNAMP.[/straws]

 

[Doggit]

An unexpect database error occured message, is a polite way of say "I have no effing idea what went wrong, but I'm not going to tell you that".

 

[ban-all-sheds]

I remember once I was looking at some of the kernel code in a proprietary OS - some of the error messages the developers had used were hilarious.

 

[PaulUszak]

Then I'm confused. I apologise for the technobabble comment if you're into C. Surely then you must appreciate what role exception handlers play. I've got it. Was your initial post a joke that I stupidly took seriously? I have no sense of irony

 

[ban-all-sheds]

It wasn't really a joke (I wasn't expecting anyone to find it funny) - it was a dig at the developer(s) who either decided that there were expected errors as well as unexpected ones or who simply didn't think about the semantics of their message.

 

[oldbutnotdead]

One of my favourite error messages (or Abnormal Endings) in Netware 3.12 was called something like the 'Richard E Adams Memorial Abend'.

 

[Doggit]

Now I doubt if there are many that even remember Netware 1.8, but I never got those sort of error messages.

 

[ban-all-sheds]

Then I'm confused. I apologise for the technobabble comment if you're into C.

Actually I'm not, very. The OS of wot I spoke was written in the hardware manufacturer's proprietary assembler code.

Anyway - I've been experiencing more flakiness earlier this evening, and out of interest I looked to see what Cloudflare do. I was surprised to read this in Wikipedia:

From September 2016 through February 2017, a major CloudFlare bug (nicknamed Cloudbleed) leaked sensitive data—including passwords and authentication tokens from customer websites, by sending extra data in response to web requests.[25] The leaks resulted from a buffer overflow, which occurred according to analysis by CloudFlare, on approximately 1 in every 3,300,000 HTTP requests.​

Hard or not to guard against, it's not as if buffer overflow exploitation is an obscure and little known hacking technique, given their security and attack mitigation foci you would have hoped they'd done a better job.

 

[ban-all-sheds]

Now I doubt if there are many that even remember Netware 1.8, but I never got those sort of error messages.

A lot of people that old can't even remember that they didn't unzip their fly before they ****.