No, I don't mean the use of sp_updatestats is not smart. It's a fine, quick mechanism for getting statistics updated in your system. But the procedure itself is not smart. I keep seeing stuff like "sp_updatestats knows which statistics need to be updated" and similar statements. Nope. Not true. Wanna know how I know? It's tricky. Ready? I looked at the query. It's there, in full, at the bottom of the article (2014 CTP2 version, just in case yours is slightly different, like, for example, no Hekaton logic). Let's focus on just this bit: if ((@ind_rowmodctr <> 0) or ((@is_ver_current is not null) and (@is_ver_current = 0))) The most interesting part is right at the front, @ind_rowmodctr <> 0. That value is loaded with the cursor and comes from sys.sysindexes and the rowmodctr column…
Earlier this week I introduced the concept of Managed Backups (and caused less of a turmoil than I thought I would). Now I want to show you how it works. It's really simple and quite well documented. Before you get to the, insanely simple, task of actually enabling Managed Backup, you will need to go through the prerequisites. First, and this should be obvious, but I'll state it, just in case, you need to set up an Azure storage account. That's so insanely straight forward that I'm not going to say more. Then, you have to set up encryption on your system. I used these commands to prep it: CREATE MASTER KEY ENCRYPTION BY PASSWORD = '$qlserver2012queryperformancetuning'; CREATE CERTIFICATE CloudDojoCert WITH SUBJECT = 'Backup Encryption Certificate'; Again, shouldn't have to…
It's kind of fun to see Azure development artifacts on display. I've posted about them before, a couple of times. I'm starting to finally get systematized about the whole thing, just so I can see stuff as it changes rather than discover them by accident or get told about them by someone else. Here's a little query I'm running to see when system views were last modified: SELECT av.name, av.create_date, av.modify_date FROM sys.all_views AS av ORDER BY av.modify_date DESC; The most recent stack of changes are here: I'll keep an eye on them to see what I can spot about interesting new functionality. I also compared the listing of all views in Azure to those on a SQL Server 2012 instance and came up with a list of differences. These…
KILT DAY! Today we have to eat our vegetables and then get lots and lots of sweet desert. Or. Today we hear about PASS Finances as a part of the official annual meeting and then we get to hear Dr. David Dewitt speak (completely and utterly getting our nerd on and squeeing like teenage girls at a Bieber concert). I will be live-blogging this event, so watch this space. 8:20: Douglas McDowell kicks off the key note today. Â the vast majority of the money that runs PASS comes from the Summit. That's right, by attending the Summit you're also supporting the organization. The Business Analytics Conference, which kicked off this year also provides quite a bit more money to the organization. 8:25: PASS has changed its budgeting process. At this…
I am liveblogging the keynote from the bloggers table at the PASS Summit again this year. Just keep scrolling. Watching the introduction video as people trickle in. All the other bloggers are setting up. I get in early. I didn't rearrange the seats this year. I see others doing it now. 8:11: Watching the videos of all the attendees registering and meeting people at the start of the event and last night's welcome reception is awesome and fun. 8:21: The lights go down and the videos of what everyone is looking forward to at the Summit. In keeping with our location, right next to the NASCAR Hall of Fame, we've got a bit of a race theme going on. We're seeing current PASS President, Bill Graziano having a dream about…
First thing, there are no bad operators, just bad parents, uh, I mean query writers, or database designers, or ORM tools. Why do I say this? Because all the operators within a query execution plan serve a purpose. They are there to fulfill a task. Depending on where and when you see them, they're doing exactly what you ask of them. The issues come up because you're asking them to do a task that they may not be well suited for. This comes from inappropriate structures and inappropriate code. Lazy spools are not really bad (that was just link bait). In fact, depending on the query, what's being done, how you're retrieving data, what data is being retrieved, the lazy spool is actually awesome. But, it's good to know what…
I'm honestly not crazy about dynamic T-SQL within stored procedures. There are just a few too many opportunities to mess it up with dire circumstances to your server and your data. However, I absolutely recognize that dynamic T-SQL may be needed, and, in some situations, the best way to solve a problem. If you must use dynamic T-SQL, there are ways that are much more efficient than others. The very best thing you can do if you need to build dynamic strings to execute T-SQL in your stored procedures is use sp_executesql. The main reason I advocate for sp_executesql is because you can build out completely dynamic strings of T-SQL, but, you can still take advantage of parameters. Parameters help you avoid a chat with the parents of Bobby Tables…
Microsoft has been pretty clear about their commitment to the entire Azure infrastructure. The updates to Azure come out on a massively accelerated schedule. Because of this, they're doing lots of code on lots of things that may, one day, end up in your full blown SQL Server instance, but are currently only available in Windows Azure SQL Database. This is because of that accelerated schedule. It frees Microsoft developers up to experiment a little. I saw some evidence of it the other day. I had been working on a series of queries for the pre-conference seminar that I helped put on at TechEd (and one that I'm doing for the PASS Summit). When I write queries, I use SQL Prompt. Sorry to be plugging Red Gate products on the…
The very concept of the Windows Azure SQL Database (WASD) is predicated on the up-time created by having three active copies of your database. Should there be a hardware or software failure that would cause the primary replica to go down, your database gets moved to one of the secondary replicas which has been maintaining a copy of the data from the primary replica. In theory, the worst thing that happens is that you have to retry a query. In fact, building that sort of resilience into your code is a pretty fundamental aspect of working with WASD. I was asked the question, how do you tell if your database has been moved between replicas. I didn't have a complete answer, so I set out to find one. The first, more obvious…
I have lists. Lots of lists. I even have them in different locations sometimes. Some of them are carefully written down in my notebook, others are typed into OneNote and I've been experimenting with Remember the Milk and Trello (Trello is winning). These lists include ideas for presentations, blogs, articles. Notes from sessions I've attended or meetings. Lots and lots of plans and ideas and all that sort of stuff. I try to keep it organized, but sometimes it runs away from me. However, I find writing things down helps me to keep things organized. Between very carefully scheduling out my calendar and all these notes, I only occasionally completely drop the ball. One ball I dropped was coming up with some goals, some plans, for 2012. I just plowed…