17Mar 2025 by Grant Fritchey No Comments

Can You See Table Valued Parameters in Extended Events?

SQL Server, You Can't Do That In Profiler
I live for questions and this was an interesting one. Can you see Table Valued Parameters that have been passed in to Extended Events? I literally have no idea. I'm sure we'll see something, I just don't know what. Time to find out. Table Valued Parameters I don't want to get in to whether or not table valued parameters are a good or bad thing. Like anything else, I'm sure they can be used for good or for evil. However, just like knowing what value was passed to an integer, I can see why you may want to know what was passed in to a table valued parameter. To get started, let's create a table type: CREATE TYPE ErrorList AS TABLE ( ErrorTime DATETIME, UserName sysname, ErrorNumber INT, ErrorMessage NVARCHAR(4000)…
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16Sep 2024 by Grant Fritchey No Comments

Can You See Who Forced a Plan

SQL Server
I had an excellent group of people in Gothenburg Sweden when I taught there and I was asked: Can You See Who Forced a Plan? I didn't know the answer for certain, so I said what I always say: I don't know, but I'll see if I can find out. Query Store System Views One of the first places I'd look to see who forced a plan is the system views in Query Store. No, I don't think it'll be there, but it's worth a look. The obvious place it could be is sys.query_store_plan. After all, that's where a plan will be marked as is_forced. But you look through that and there's nothing about who forced a plan. And looking through the other views, there's nothing showing that. So, this…
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02Sep 2024 by Grant Fritchey No Comments

Missing Columns in Extended Events Live Data Explorer

SQL Server
Let me be extremely clear up front, this is not my original work. I saw this post on DBA.StackExchange.com and I wanted to share and promote it. Nice work FevziKartal. The rest of this post is just me replicating work already done by others. I just want to see it in action. Columns in Live Data Explorer Back when I wrote the 2017 version of my query performance tuning book (no link, a) get the 2022 version for reasons I'm about to explain, b) this post is just about testing FevziKartal's work, not self-promotion), I was on board with #TeamXE. Jonathan Kehayias had taken me under his wing and explained the virtues of Extended Events and I was sold. I was also grossly ignorant. I thought that the way you…
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01Jul 2024 by Grant Fritchey No Comments

Only Capture Extended Events For a Given Time

SQL Server
It's a great question. Let's say you want to capture stored procedure completions. But, you only want to capture them between 3AM and 4AM. Can you do it? Output of rpc_completed Let's create a really simple event: CREATE EVENT SESSION [RPCTimeBoxed] ON SERVER ADD EVENT sqlserver.rpc_completed(SET collect_statement=(1) WHERE ([sqlserver].[database_name]=N'AdventureWorks')); If we start this event, run some code, the output within the Data Explorer window looks like this: Just a couple of points here. Notice the fields in the event. None of them are dates or times. However, up above, we get the timestamp column. Done, right? Let's use that. But first, what does AI, through CoPilot tell me? CoPilot To The Rescue? I asked CoPilot. It took a couple of refinements to get it on board with the idea that…
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14Sep 2023 by Grant Fritchey 3 Comments

T-SQL Tuesday #166: Why Not Extended Events?

SQL Server
With 165 T-SQL Tuesday events, two, just two, this one, T-SQL Tuesday #166, and another one back in 2018 or 2019 (I forget and I'm far too lazy to go look) have been on Extended Events. At conferences I'm frequently the only one doing sessions on Extended Events (although, sometimes, Erin Stellato is there, presenting a better session than mine). I did a session at SQL Konferenz in Germany earlier this week on Extended Events. Hanging out in the hallway at the event (which was great by the way), I was talking with some consultants. Here's their paraphrased (probably badly) story: "I was working with an organization just a few weeks back. They found that Trace was truncating the text on some queries they were trying to track. I asked…
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11Sep 2023 by Grant Fritchey 4 Comments

T-SQL Tuesday #166: Extended Events

T-SQL
When I was put on the list to host September's T-SQL Tuesday, well, I forgot to put it in my calendar. So I'm late (and in the doghouse with Steve). Because of this, I'm going to bend the rules a little (sorry Steve) and give you a few days to get your posts together. In theory, they're all due tomorrow, Tuesday, September 12. However, let's say they're all due by the end of the day on Thursday, September 14th. My apologies for being tardy. I'll still post a roundup on Friday. So, what's the topic for T-SQL Tuesday. Well, it's in the title, Extended Events. Let's talk about it. Why Extended Events? As anyone who has read my blog or books, or seen me speak, you'll know that I've got…
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27Feb 2023 by Grant Fritchey No Comments

What Happens on Azure SQL Database?

Azure, SQL Server
Last week I posted the results from using Extended Events to snoop on what happens inside an AWS RDS database. This week, I'm taking a look at what happens on Azure SQL Database. I'm using the same toolset again, if for no other reason that I'm consistent in my approach. So it's basically just rpc_completed & sql_batch_completed on the database in question. Let's check out the results. What Happens on Azure SQL Database I would be doing the same thing as before, breaking apart the batch commands from the stored procs and/or prepared statements. However, after 48 hours, I only have 116 of both, so I'm just going to combine them this time. The batch called most frequently, for a whopping total of 8 times over 48 hours, isn't even…
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05Apr 2021 by Grant Fritchey 1 Comment

Extended Events: Embrace the XML

SQL Server
While XML is, without a doubt, a giant pain in the bottom, sometimes, the best way to deal with Extended Events is to simply embrace the XML. Now, I know, just last week, I suggested ways to avoid the XML. I will freely admit, that is my default position. If I can avoid the XML, I will certainly do it. However, there are times where just embracing the XML works out nicely. Let's talk about it a little. Copy This Query I have a theory. It goes like this: There has only, ever, been a single XML query written from scratch. All other XML queries are just copied from that one and then edited to do what is necessary OK. Maybe that's not entirely true. In fact, I know it's…
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29Mar 2021 by Grant Fritchey 9 Comments

Extended Events: Avoid the XML

SQL Server, Tools
One story I hear over and over goes like this: I tried setting up Extended Events, but then I saw the output was XML so I stopped. Look, I get it. I don't like XML either. It's a pain to work with. It's actively difficult to write queries against it. If there weren't a ton of ways to avoid the XML, yeah, I would never advocate for Extended Events. However, here we are, I have ten pages of blog posts that at least mention Extended Events. Why? Because I avoid the XML (most of the time). Lots of other people do as well. You can too. Let's see how. Live Data Window I have a video that goes into this in detail right here. But the core concept is simple.…
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23Mar 2020 by Grant Fritchey No Comments

Extended Events: Live Data Explorer, Grouping

SQL Server, You Can't Do That In Profiler
Of all the things that Extended Events does, I've found the ability to quickly and easily gather a little bit of data and then use the Data Explorer window Live Data grouping to aggregate it to be one of the greatest. Sure, if we're talking about using Extended Events on a busy production server, this method probably isn't going to work well. There, you are going to be better off querying the XML (I know, I know, but I have ways to help there too). But in development, when doing testing and query tuning, the Live Data window is a gift of the gods on par with fire or beer (it's not as good as whiskey). Live Data Grouping Let's imagine a scenario like this. You're working on some query…
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