Search Results for: query store

PASS Summit Day 3: Dr. David Dewitt

Two quick points, I'm putting this blog together using the Surface.. ooh... and this isn't a keynote, but a spotlight session at the Summit. Still, I thought I would live blog my thoughts because I've done it for every time Dr. Dewitt has spoken at the Summit. Right off, he has a slide with a little brain character representing himself. But, we're talking PolyBase, and futures. This is basically a way to combine hadoop unstructured nosql data with structured storage within SQL Server. Mostly this is within the new Parallel Datawarehouse. But it's coming to all of SQL Server, so we need to learn this. The information ties directly back to what was presented at yesterday's keynote. HDFS is the file system. On top of that a framework for executing…
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PASS Summit 2012 Day 1

We're off and running here at the PASS Summit. New this year is live streaming all day. Bill Graziano is introducing the Summit. More importantly, he's introducing PASS. Further, he's introducing speakers to everyone. He doesn't mean just speakers at the summit, but anyone who has spoken at a SQL Saturday or a user group, and it was a scary large group of people. PASS has created a new web site to make it easier to find local Chapters. Track one down. On the one hand, it's weird that we're sitting at the PASS Summit and introducing the PASS organization, but I think they're right to do it. It's a great organization and I'm always surprised at how many people don't know about it. Bill's big announcement is the all…
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Conference in Florida: SQL Server Live

This conference is new to me. In case it's new to you, I thought I'd take a moment to point it out. Mostly because I'll be presenting there and I love talking to anyone who has actually read any of the blather I post on my blog. If you want to get together in the land of sunshine in December (don't tell Mrs. Scary but I'm looking forward to this one, winter in New England is awful), then click here to register. If you do it now you save $500, so it's a good time to take care of it. I'll be presenting two different sessions. One is on backups and restores for the accidental DBA. I'll go over the important stuff to get you started protecting your company's data…
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Please, Call Me Richard

I presented a session at the SQL Saturday event in Oklahoma City last weekend. The event itself was pretty good. The organizers put everything together pretty well and the venue was quite nice. Plus, since I grew up in Oklahoma (Tulsa), it was a chance to go home. The event was good, but my presentation went a little downhill. The name of the session is "Top Tips for Better Stored Procedure Performance." I should rename it to just say "T-SQL Query Performance" because it's not focused on stored procedures, but on queries. The presentation is 1/3 talking about how you write your queries, naming syntax, formatting, etc. The second 2/3 is all about common mistakes made in writing T-SQL such as using NO_LOCK everywhere, nesting views, joining and nesting multi-statement…
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Does Encryption Affect Seeing Statements in Deadlock Graphs?

Good question. I don’t have a clue. So let’s set up a test. I’ll create this stored procedure: CREATE PROCEDURE DL2e WITH ENCRYPTION AS BEGIN TRANSACTION UPDATE Purchasing.PurchaseOrderDetail SET OrderQty = 2 WHERE ProductID = 448 AND PurchaseOrderID = 1255; Then I’ll execute things in the following order. From one connection this query: UPDATE Purchasing.PurchaseOrderHeader SET Freight = Freight * 0.9 --9% discount on shipping WHERE PurchaseOrderID = 1255; From a second connection, my stored procedure: EXEC dbo.dl2e; Then, back on the first connection, this query: UPDATE Purchasing.PurchaseOrderDetail SET OrderQty = 4 WHERE ProductID = 448 AND PurchaseOrderID = 1255; That will generate a deadlock. It’s a straight-forward classic deadlock. I’m using extended events to capture the deadlock graph and the output looks like this: <deadlock> <victim-list> <victimProcess id="process472310928" />…
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Is Dynamic T-SQL a Good Design Pattern?

In a recent discussion it was suggested to me that not only is dynamic T-SQL useful for things like catch-all queries or some really hard to solve problems involving variable table lists, but is, in fact, a perfectly acceptable design pattern for all queries against a database. Note, in this case, we’re not talking about an ORM tool which takes control of the system through parameterized queries, but rather an intentional choice to build nothing but dynamic T-SQL directly on the system. To me, this was immediately problematic. I absolutely agree, you’re going to have dynamic T-SQL for some of those odd-ball catch-all search queries. But to simply expand that out to include all your queries is nuts. There really is a reason that stored procedures exist, and it’s not…
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Which SELECT * Is Better?

The short answer is, of course, none of them, but testing is the only way to be sure. I was asked, what happens when you run ‘SELECT *’ against a clustered index, a non-clustered index, and a columnstore index. The answer is somewhat dependent on whether or not you have a WHERE clause and whether or not the indexes are selective (well, the clustered & non-clustered indexes, columnstore is a little different). Let’s start with the simplest: SELECT    * FROM    Production.ProductListPriceHistory AS plph; This query results in a clustered index scan and 5 logical reads. To do the same thing with a non-clustered index… well, we’ll have to cheat and it’ll look silly, but let’s be fair. Here’s my new index: CREATE NONCLUSTERED INDEX TestIndex ON Production.ProductListPriceHistory (ProductID,StartDate,EndDate,ListPrice,ModifiedDate); When I…
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Database Backups: Things You Need To Do Now

I want to say a few things about database backups that you need to know. Wait a minute, haven’t you written about backups before? Why, yes. Yes I have. Aaand… you’re doing it again because? Have you noticed the shocking number of questions that come up on SQL Server Central and #sqlhelp regarding backups? Have you noticed the incredibly huge number of people who don’t have backups at all? That’s why. To get the word out. Oh, good point. Carry on. Because backups are so easy, people tend to discount them. That is, until they need them. Then, suddenly, they become extremely important. Here’s a suggestion: Make databases important now. Learn how SQL Server backup works. Make sure you have backups on your systems. Make sure you have the appropriate…
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PASS Keynote Day #3: Dr. Dewitt

And we’re off. We opened with a video of people saying “Connect, Share, Learn” and “This, is Community” Rob Farley & Buck Woody came out with a song about long running queries. [8:20]Wayne Snyder has been working with the PASS organization since 1999. He spoke at the first PASS Summit and he’s been on the board forever. He has finally hit the point as immediate-past president where he has to leave the board. We’ve got a great little thank you for him from all sorts of people. Wayne is a magnificent guy, seriously. If you see him, thank him for his service. [8:28]We have a new executive committee, Bill Graziano as President, WHOOP, Douglas McDowell is Executive Vice-President and Thomas LaRock is VP of Marketing and finally, Rushabh Mehta is…
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PASS Summit 2011 Abstracts

I’ve put in several abstracts for the 2011 Summit. This year we’re voting for preferred sessions. If you’re interested in any of the ones I’ve listed below, please consider giving me a vote.I was very kindly invited to submit for a spotlight session (for which I am very grateful and humbled, again) so I put two in for that. I also put in for two regular sessions. This year, for the first time I put in not one, but two abstracts for all day pre/post-conference sessions. One of them was put together as a partnership between Gail Shaw (blog|twitter) and myself. I’m excited by that one. I love speaking and I really hope I make the cut. In the interest of sharing, these are the abstracts I’ve submitted: Spotlight: DMOs…
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