19Sep 2022 by Grant Fritchey No Comments

Extended Events for Anything but Query Tuning: bulk_insert_usage

SQL Server
Wouldn't it be great to be able to directly monitor specific behaviors within SQL Server, like, oh, I don't know, knowing exactly when, and how, someone is using BULK INSERT? Well, you can, thanks to Extended Events through the bulk_insert_usage event. Bulk_insert_usage The BULK INSERT command is extremely useful within SQL Server. It's a way to move data into the database and provide some formatting on the way, efficiently, all through T-SQL. Hard to argue with the utility. Obviously, if you're doing traditional data collection through Trace or Extended Events, you'll see BULK INSERT commands within the T-SQL. However, Extended Events provides a specific event that tracks just the behavior of BULK INSERT: bulk_insert_usage. Documentation on this is somewhat sparse. Some of the best is from a standard source, Jason…
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05Sep 2022 by Grant Fritchey No Comments

Database Fundamentals #33: Check Constraints from the GUI

Database Fundamentals, SQL Server
The other types of constraints are referred to as check constraints. They limit the data by defining a logical operation that checks the state of the data prior to allowing an insert or update to the table. The logical operation is not against other tables. The logic can be against multiple columns in the same table. Let’s start with a simple example. The business has determined that the transactions it’s recording will never be less than $10. As part of the business definition, they would like a constraint put in place that limits the TransactionAmount values in the Finance.FinancialTransaction table to only accept values that are greater than $10. Let’s create this constraint using the GUI and again, in the next post, using T-SQL. Check Constraint with the GUI We’ll…
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15Aug 2022 by Grant Fritchey 1 Comment

Distributed Replay: The Little Engine That Almost Could

SQL Server
Honestly, sincerely, no kidding, I love Distributed Replay. Yes, I get it. Proof positive I'm an idiot. As we needed proof. To be a little fair to me, I love what Distributed Replay could have been, with a little more love. However, fact is, it's on the deprecation list for 2022. Which means, what minimal amount of love, if any, that Microsoft was giving to it, it's all gone, forever. Unlike the Little Engine That Could, turns out that Distributed Replay was the Little Engine That Almost Could, But Didn't. Really Didn't. Let's discuss it a bit. Distributed Replay The concept is wonderful. Capture a bunch of queries from your production system. Replay them on a non-production system for testing. Add in the idea of being able to chain together…
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08Aug 2022 by Grant Fritchey No Comments

Extended Events for Anything but Query Tuning: Object Changes

SQL Server
I hear this one all the time: How do I find out who implemented object changes? I also get: Can I see the query that caused object changes? Let's take a look at how you might audit who is doing what and how to your databases. Object Changes in Extended Events If you open up the New Session window for Extended Events in SSMS, the easy way to track down events is to simply type into the box. Here, we care about capturing object changes, so I'm going to simply type object, then scroll a bit: There we are object_altered, object_created and object_deleted. These are the same events that you would see in Trace. Let's use the GUI and take a quick look at what fields they capture: That's in…
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25Jul 2022 by Grant Fritchey No Comments

Database Fundamentals #32: Create Unique Constraints with T-SQL

Database Fundamentals, SQL Server
In the last Database Fundamentals post, I explained what a unique constraint was and how you can create them using the GUI. Using TSQL to create a constraint is very similar to the primary key and foreign key constraints that you created in this post. You can use either the ALTER TABLE command or create the constraint when you make the table with the CREATE TABLE command. Using CREATE TABLE to Make a Unique Constraint There aren’t any new tables we need for this post, so we’ll create a table that we can drop immediately as soon as we’re done experimenting. You should already be familiar with the CREATE TABLE statement (or follow the link above): CREATE TABLE dbo.ConstraintTest ( TestName VARCHAR(50), CONSTRAINT UniqueName UNIQUE (TestName) ); This script creates…
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11Jul 2022 by Grant Fritchey No Comments

Extended Events for Anything But Query Tuning: xml_deadlock_report_filtered

SQL Server
One of my favorite little bits of information about Extended Events is the fact that everyone running a full instance of SQL Server has deadlock information available to them, even if they never enabled Trace Flag 1222 through the system_health session. That captures the xml_deadlock_report which has the full deadlock graph. However, what if you want to capture deadlock info, but, you're dealing the GDPR, and transmitting query values could be problematic? Enter xml_deadlock_report_filtered. xml_deadlock_report_filtered If you do a search for this event, you're not going to find much. Doesn't seem like anyone, including Microsoft, has bothered to document it. This is not going to be a comprehensive definition for all things xml_deadlock_report_filtered. However, I can show you why you might want to use it. This is a port of…
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05Jul 2022 by Grant Fritchey 2 Comments

Extended Events for Anything But Query Tuning: Unique Constraint Violations

SQL Server
Most of the time when I talk about or demo Extended Events, I spend more time talking about query tuning (I have a problem). However, there are tons of things that you can do with Extended Events. Here's a little one that came up, auditing unique constraint violations. Unique Constraint Violations Whether we're talking a primary key or just a constraint, the error you get is number 2627 when you attempt to add a non-unique value. So, the code for a simple way to track this in Extended Events would look like this: CREATE EVENT SESSION [UniqueConstraintViolation] ON SERVER ADD EVENT sqlserver.error_reported (WHERE ([error_number] = (2627))); That's it. That's all you need. Probably, it'd be a good idea to output this to a file (that's usually what I do). However,…
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11Apr 2022 by Grant Fritchey 7 Comments

Query Tuning and Easy Solutions

SQL Server
TLDR: There ain't one. I was privileged last week to be able to present a couple of sessions at the SQL Server and Azure SQL Conference (great event, I recommend it). One of my sessions was an intro to query tuning. Basically, I went through a bunch of common code smells and suggested different possible solutions. The one thing that came up, both from my own stories and the questions from the (engaged) audience, is just how much everyone wants a magic, run fast, switch. Query Tuning The Easy Way Here you go. The single easiest way to make your queries run faster: Just throw money at the problem. Buy more hardware. Buy bigger hardware. Get more disks and disk controllers (not just more disks). Go to the next highest…
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07Mar 2022 by Grant Fritchey 4 Comments

Query Plans in Azure Data Studio

SQL Server
I have long been a fan of Azure Data Studio, but one shortcoming has kept me from truly adopting it: Query Plans in Azure Data Studio. Sure, there was a plug-in you could install. Also, you could use a somewhat truncated version of Plan Explorer, but all I wanted was for SQL Server Management Studio plans to be query plans in Azure Data Studio. Go and get version 1.35 of the tool. Right now. DUDE! You have 1.35 of Azure Data Studio? Cool. Now, go to the menu bar. Click on "File." Click on "Preferences". Click on "Settings". Now, type the following into the search box: workbench editor enable preview. You should see this: Check the box below where it says "Workbench > Editor: Enable Preview" just like I have…
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28Feb 2022 by Grant Fritchey No Comments

Database Fundamentals #31: Unique Constraints from the GUI

Database Fundamentals, SQL Server
In the last few Fundamentals posts you were introduced to a couple of ways to limit and control the data stored in the tables in your database. A primary key won’t allow a duplicate value. A foreign key won’t allow a value to be added that doesn’t already exist in the parent table and it will prevent data from being deleted. These are types of constraints on data in your database. There are a bunch of other ways to constrain the data in an effort to ensure that the data stored is exactly what the business needs. The next few Fundamentals posts will cover several methods of limiting data. Unique Constraints to Stop Duplicates When the concept of the primary key was introduced earlier in the series, two different types…
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