Meme Monday: I got 99 problems but a disk ain’t one

Last month Thomas LaRock ( blog | @SQLRockstar ) started a series called Meme Monday, and this week the task is to list nine things that can wrong with SQL Server that are not the result of an issue with the database file storage.

Note: The emphasis on nine reminds me of a quote from Ferris Bueller’s Day Off.

Katie Bueller: Nine times?
Ed Rooney: Nine times.
Katie Bueller: I don’t remember him being sick nine times.

I digress…

Here are my nine, in the order they came to me:

User choices when searching – I have lost count of the number of times I have had to explain that it is hard to tune a query that returns over 50,000 rows.
Login issues after a failover – I’m thinking of Database Mirroring, and I know there’s a way to transfer Logins, but I’m very interested to test out contained databases in Denali to see if that makes life easier (more info from Aaron Bertrand here).
Statistics out of date – About 1 in 5 customer performance issues I work on are related to statistics (either outdated or improperly sampled).
ODBC drivers – In case you’re wondering, I’ve seen orphaned sessions (holding locks and blocking) when using the initial SQL 2005 ODBC drivers (we recommend the ones released in 2008).
VMWare configuration – See my recent post, Some Errors Are Not What They Seem.
Too little memory – I’ve only seen this as a customer problem once…PLE was below 30 at times…a lot of churn in memory.
30+ tables joined in a query – Need I say more?
Running reports against the Production database – For the love of Pete, set up a reporting database.
SQLAgent not running – When the Agent doesn’t run, important jobs like transaction log backups don’t run…and inevitably you can run out of disk space. Sad face.

This post, and the topic in general, is a great reminder of how to approach trouble-shooting a SQL Server issue. Keep your mind open, look for clues in the data, and initially rule out problems rather than try to prove one.