The SQL Query Optimizer – when Logical Order can get it wrong

It’s very easy to get in the habit of imagining the way that a query should work based on the Logical Order of query processing – the idea that the FROM clause gets evaluated first, followed by the WHERE clause, GROUP BY, and so on – finally ending with whatever is in the SELECT clause. … Continue reading The SQL Query Optimizer – when Logical Order can get it wrong

Portfolio changeover time for the PASS board

The last PASS board meeting for the year has happened, and the portfolio handovers are well under way. Sadly, having new board members elected means having existing board members step down, and this last board meeting was the last one for both Allen Kinsel (@sqlinsaneo) and Kendal van Dyke (@sqldba). In 2012, these guys had … Continue reading Portfolio changeover time for the PASS board

SQL Replication demystified

I spent some time explaining SQL Server Replication to someone recently. They said they hadn’t ever really understood the concepts, and that I’d managed to help. It’s inspired me to write a post that I wouldn’t normally do – a “101” post. I’m not trying to do a fully comprehensive piece on replication, just enough … Continue reading SQL Replication demystified

The MCM lab exam – two days later

Readers of my blog, or followers on Twitter will know I took the MCM Lab exam a couple of days ago. I let people know I was doing the exam, rather than doing the ‘normal’ thing of doing it in secret and hoping no-one found out until a successful result had been published. Oh, and … Continue reading The MCM lab exam – two days later

MCM Lab exam this week

In two days I’ll’ve finished the MCM Lab exam, 88-971. If you do an internet search for 88-971, it’ll tell you the answer is –883. Obviously. It’ll also give you a link to the actual exam page, which is useful too, once you’ve finished being distracted by the calculator instead of going to the thing … Continue reading MCM Lab exam this week

Joins in single-table queries

Tables are only metadata. They don’t store data. I’ve written something about this before, but I want to take a viewpoint of this idea around the topic of joins, especially since it’s the topic for T-SQL Tuesday this month. Hosted this time by Sebastian Meine (@sqlity), who has a whole series on joins this month. … Continue reading Joins in single-table queries