A better question would have been, what is the result of:

SELECT CONVERT(DECIMAL, 1.2)

I was correct, but did not like this question. None of the options do anything, so they are all equivalent.

Unfortunately, it isn't always the same table, and I don't want to stop the other 3 from making legit changes.

Is there a possibility a single user running a single query could cause significant blocking/locking issues? I would think SQL Server takes care of this.

I do know something else...

As I said, no one could do anything with sql server, including checking for locks or other activity.

No other processes were using more than 1% of the CPU.

Speculation is appreciated.

I don't think this was contention however. Soon after the problem started, no one could do anything, so they mostly stopped trying. We also shut down...

I remember seeing this, and ending up switching back to count(*), but I cannot remember why - it may have been for accuracy problems, and I am not sure which...

If you get the same problem, don't copy/paste directly into MSSMS, copy to notepad first, and fix anything that should be a space, but isn't.

Am I the only one that gets

Msg 102, Level 15, State 1, Line 2

Incorrect syntax near '?'.

when trying to run this?

Thanks!