Category: Tech and Learning

Tip: Concatenate rows with XML, or COALESCE

Edit: I went and changed the first query without paying close enough attention. I’ve fixed the explanation and the query. Concatenate rows with XML I still reference my Forgotten T-SQL Cheat Sheet, especially for the XML trick that turns a set of rows into a list. The T-SQL Cheat Sheet example uses a parent-child table combination, […]

Why don’t they make the optimizer faster? (An essay on nested views)

We got a question recently that basically boiled down to this: Nested views shouldn’t be such a performance suck. Why doesn’t Microsoft make the optimizer deal with nested views better? We’ve looked into this a good deal – nested views are one of my pet peeves, and I’ve blogged about it at least a couple of times (see Detangling Nested Views and […]

Tip: RECOVERY_PENDING is not the same as RECOVERING

I’ve seen this mistake more than once, from DBAs with a middling to fair amount of experience. So it bears repeating. RECOVERY_PENDING is very different from RECOVERING. Definitions RECOVERING means that things are happening, and all may be well. “Database is being recovered. The recovering process is a transient state; the database will automatically become online if […]