21Apr 2015 by Grant Fritchey 5 Comments

Query Hash Formula Changes Between Versions

SQL Server
The question came up on SQL Server Central that someone wanted to track queries on their 2008R2 instance and on their 2014 instance in order to validate performance after an upgrade. The plan was to use query hash values. I was curious, so I set up a quick test. First, I spun up two VMs in Azure, both A1, both Enterprise, but one for 2008R2 and one for 2014. Then, I grabbed a generic query that runs against DMVs: SELECT TOP 10 SUBSTRING(dest.text, (deqs.statement_start_offset / 2) + 1, (CASE deqs.statement_end_offset WHEN -1 THEN DATALENGTH(dest.text) ELSE deqs.statement_end_offset - deqs.statement_start_offset END) / 2 + 1) AS querystatement, deqp.query_plan, deqs.query_hash, deqs.execution_count, deqs.last_elapsed_time, deqs.last_logical_reads, deqs.last_logical_writes, deqs.last_worker_time, deqs.max_elapsed_time, deqs.max_logical_reads, deqs.max_logical_writes, deqs.max_worker_time, deqs.total_elapsed_time, deqs.total_logical_reads, deqs.total_logical_writes, deqs.total_worker_time FROM sys.dm_exec_query_stats AS deqs CROSS APPLY sys.dm_exec_query_plan(deqs.plan_handle) AS deqp CROSS APPLY…
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16Apr 2015 by Grant Fritchey No Comments

Azure SQL Database v12 and SQL Magazine

Azure
I spend many of my evenings researching and writing. Sometimes it's writing new books. Sometimes it's fixing and rewriting old books. Occasionally it's a blog post like this one. Lately, it's been a series of articles for SQL Magazine that are all about the new functionality available in Azure SQL Database v12 that was released in February for most data centers in Azure. It's a whole new ball game. Check out my introductory article for v12 and the one on DMVs in Azure. I have more coming up on CLR in Azure, getting started, PowerShell, DBCC, T-SQL enhancements, Premium Tier and more. I'll also get into "old" functionality like backup and restore. I'll also explore new functionality, Azure is nothing if not dynamic, as becomes widely available. I know a…
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13Apr 2015 by Grant Fritchey 2 Comments

Azure SQL Database Firewall Settings

Azure
The new portal for managing Azure is pretty. I'm not sure I'm in love with it, but it's pretty. However, one thing that I have to access regularly is the firewall settings for my Azure SQL Database. I do demos from all over the place. I never know what my IP address is going to be. Rather than expose everything, I just set up whatever IP address I'm on and then remove it later. The old portal made this easy. The new one... not so much. So, let's get this down real quick. Assuming you connect to the new portal and go straight to your database, you'll see this image showing you the database and the server it's on: You won't see anything else that suggests FIREWALL. But, you can…
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10Apr 2015 by Grant Fritchey 5 Comments

I Am Grateful For

Professional Development
I decided in January that I would write regularly about people that I'm grateful for. Now it's April. Oops. The concepts are simple and science based. Positive emotions help your clarity of thought. Further, your moods and actions extend out through your network to the third layer. With that in mind, I want to think more clearly and the most direct path to positive thoughts and emotions being gratitude, I'm attempting to focus and publicize my gratitude by publicly sharing it through these blogs (in short, I'm trying to tune my brain like I would tune a query). I am grateful for Tim Ford (b|t). Tim is a great guy. Further, Tim can be patient with thick headed dorks (raising my hand). For example, among all the other stuff Tim does…
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07Apr 2015 by Grant Fritchey No Comments

Error: Unknown Property ismemoryoptimized

Azure
If you're starting the process of moving your databases in Azure SQL Databast to v12, you need to do one thing. Make sure you have SQL Server 2014 CU5 or better installed on your machine with Management Studio (current list of updates). Otherwise, like me, you'll be looking at the above error. Just a quick blog post to help out. I saw this error, did a search, and didn't hit a single entry telling me what to do. I started the install of CU6 (I needed to catch up on cumulative updates anyway). While that was happening, I went to Twitter and posted to #sqlhelp to see if anyone else had hit this. I got a response from Amit Banarjee pointing me to this MSDB blog on the topic, reinforcing…
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06Apr 2015 by Grant Fritchey 8 Comments

Constraints and SELECT Statements

Azure, SQL Server, T-SQL
I've posted previously about how a foreign key constraint can change how a SELECT query behaves. Logically that just makes sense. But other types of constraints don't affect execution plans do they? Yes. Let's take this constraint as an example: ALTER TABLE Sales.SalesOrderDetail WITH CHECK ADD  CONSTRAINT CK_SalesOrderDetail_UnitPrice CHECK  ((UnitPrice>=(0.00))) That will ensure that no values less than zero can slip in there. We can even validate it: INSERT Sales.SalesOrderDetail (SalesOrderID, CarrierTrackingNumber, OrderQty, ProductID, SpecialOfferID, UnitPrice, UnitPriceDiscount, rowguid, ModifiedDate ) VALUES (60176, -- SalesOrderID - int N'XYZ123', -- CarrierTrackingNumber - nvarchar(25) 1, -- OrderQty - smallint 873, -- ProductID - int 1, -- SpecialOfferID - int -22, -- UnitPrice - money 0.0, -- UnitPriceDiscount - money NEWID(), -- rowguid - uniqueidentifier GETDATE() -- ModifiedDate - datetime ); Will give me…
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03Apr 2015 by Grant Fritchey No Comments

Speaker of the Month: April 2015

Professional Development
One of my favorite events of the year is the SQL Saturday in Silicon Valley. They've had four of them and I've gone to three (had to miss last year, scheduling conflict). It's a fantastic event and Mark Ginnebaugh (b|t) does a great job putting it together. In fact, this year, we got to listen to Ross Mistry and T.K. Rengarajan have a "fireside chat" for the keynote. For those who don't know, Mr. Rengarajan is just a VP at Microsoft. Yeah, he simply runs the ENTIRE FLIPPING AZURE DATA PLATFORM. That's all. They had a few demos and showed us unreleased code and new versions of SSMS not yet available publicly (including functionality around Query Store and execution plans, my little heart was going pitter-pat). Anyway, if you missed it, you…
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31Mar 2015 by Grant Fritchey 6 Comments

PASS Board Update: March 2015

PASS
Hello all, It's been a while since my last update. Sorry. I've just been traveling and presenting and working on books and this slipped through the cracks a bit. I'll try to do better in the future. Nothing major to report. As a board member I've been working primarily on two things. First, I've been polishing my goals for the Chapters Portfolio. I'll publish those below. Next, I'm working on the budget for Chapters for next year. In between times, a lot of what I do, is work with Regional Mentors (RM) and Chapter Leaders (CL) on an individual basis. As much as the stuff that PASS as an organization is involved with is around technology, the PASS organization, especially Chapters, is all about people. And you know how people…
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30Mar 2015 by Grant Fritchey No Comments

Does the New Cardinality Estimator Reduce Bad Parameter Sniffing

T-SQL
No. Next question. Although, that answer can be slightly, ever so slightly, nuanced... Parameter sniffing is a good thing. But, like a good wine, parameter sniffing can go bad. It always comes down to your statistics. A very accurate set of statistics with very little data skew (some values that have radically more/less data than other values) and a very even distribution (most values have approximately similar cardinality), and parameter sniffing is your bestest buddy on the planet (next to a tested backup). But, introduce some data skew, let the stats get wildly out of date, or suffer from seriously uneven distribution, and suddenly your best friend is doing unspeakable things to your performance (kind of like multi-statement table valued user defined functions). SQL Server 2014 has the first upgrade…
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25Mar 2015 by Grant Fritchey 1 Comment

Toshiba Portege Z301-A Review

Tools
Last year I purchased a Lenovo W530. Nightmares then ensued. Nice laptop if you just want to use it as a laptop, and only a laptop. Horror show if you need to present from it. So, I replaced it with an HP... which also gave me some troubles (try presenting with your laptop bricked in front of your boss AND 100 people), but that's OK because I dropped it the next day (totally by accident, it had just worked great all day, I was happy with it, mostly). So there I was, laptop free and in need of something that would let me work, present, and be an all round road warrior. PLUS, I had just broke a laptop and was feeling bad that company would be replacing it. So…
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