24Mar 2025 by Grant Fritchey 2 Comments

Can You Tell Why a Plan Didn’t Go Parallel?

SQL Server
Let's face it, most of the time, you probably don't want your SQL Server execution plans to go parallel. After all, that's why, instead of adjusting the Cost Threshold for Parallelism (as you should have), you've set the Max Degree of Parallelism to 1 (I see you out there). However, some of you recognize that, in fact, some queries need to run in Parallel. Yet, sometimes, a query you think should run in parallel doesn't. Can you tell why a plan didn't go parallel? If It's Not Parallel, Why Not? The good news is, this question is really simple to answer. I'm sure you'll be shocked when I tell you that it's right there in the execution plan. The bad news is, you're going to have to open up the…
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20Mar 2025 by Grant Fritchey 3 Comments

Sic Transit Gloria Community

Professional Development
When Covid took out the PASS organization, I had someone say to me, "Well, that's the end of the data community." My response was pretty simple, "Nope. The community is the people, and they're not going anywhere." I was right. And I was wrong, but not because of PASS. Splintered I was asked recently, in a single word, to describe the data community. I chose 'Splintered.' Why? It's because of social media. We leaned pretty hard on having a limited number of channels for communication within the community. There were really only a couple of choices. Today though, we're scattered to the four winds. BlueSky has brought in some people. Others are on Mastodon. You'll still find people on X or Facebook. However, even more are on LinkedIn. Don't forget…
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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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13Feb 2025 by Grant Fritchey No Comments

Free PostgreSQL Performance Monitoring with pgNow

PostgreSQL
I've been putting together a new PostgreSQL session called "Performance Monitoring for the Absolute Beginner." There are several ways to get an understanding of how well your queries are running in PostgreSQL, but, frankly, all of them are a bit of a pain to someone coming from the land of Extended Events (ah, my one true love). Because of this, I saw it as an opportunity to help those just getting going in PostgreSQL. I'll be presenting it for the first time at Postgres Conference in Orlando on March 19, 2025. Come on by. Anyhoo, wouldn't it be nice to maybe have a shortcut, an easier way to look at this information? Well, there is. Redgate has been working on a completely free tool for leveraging just this sort of…
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07Oct 2024 by Grant Fritchey 4 Comments

RDS Connectivity

AWS, PostgreSQL, RDS
I travel quite a lot for work. Most of it is in the US and Europe, but I get around to other places as well. Most of the time, connectivity, while not the greatest, isn't that bad, or hard. I run a VPN on my phone and laptop. I can set up my RDS connectivity by getting whatever IP address I've been assigned, and I'm good to go. However, recently, for whatever reason, I could not make a connection to AWS RDS no matter what I tried. I even switched over to my phone. I dropped my existing database (which hurt, just a test database, but now I have to rebuild it). Nothing. I validated every single possible problem. I went through all the troubleshooting steps. Nothing. It's Nice to…
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30Sep 2024 by Grant Fritchey 5 Comments

The Only Valid Test of a Backup is a Restore

Professional Development
Please, let me reiterate: The only valid test of a backup is a restore. THE ONLY VALID TEST OF A BACKUP IS A RESTORE. I'm happy that you have backups. That's great. Can you restore them? Let's tell a story. I Play With Radios "WE KNOW! SHUT UP ABOUT IT! Damn radio people. Worse than crossfitters." Cool, cool! I won't get into the radio stuff.... too much. Just a quick setup. Please bear with me. There's an organization in the US, American Radio Relay League (ARRL). Founded back in the dawn of time, more or less the first radio club. Now, the ARRL does a lot of stuff for radio users in the US, but also everywhere, but there's controversy (when isn't there). One thing they did was build this…
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23Sep 2024 by Grant Fritchey No Comments

Additional Use for sp_statement_completed

SQL Server
Another discussion in Gothenburg (such a great group of people) around Extended Events lead to a (admittedly, tiny) idea for an additional use for sp_statement_completed. The basics for sp_statement_completed are pretty straight forward. If you want to capture a procedure's behavior, you use rpc_completed. If you want to know about the individual statements within the procedure, you use sp_statement_completed. Now, I don't recommend turning this on across the board or without some good filtering in place because, it's likely to generate quite a bit of data. However, it can be useful, including in the following manner. What Path Did I Take? I've got a silly, example, procedure here: CREATE PROC dbo.PathTest ( @Path1 INT, @Path2 INT, @Path3 INT ) AS IF @Path1 = 1 PRINT 'Path 1'; ELSE IF @Path2…
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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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26Aug 2024 by Grant Fritchey No Comments

AWS RDS PostgreSQL Restore to a Point in Time

AWS, PostgreSQL, RDS
One of the single biggest reasons to go with a Platform as a Service (PaaS) offering like AWS RDS are the things it does for you, like making it really easy to restore to a point in time. Let's take a look at it. Restore to a Point in Time When connect up to the console and look at your databases, all you have to do is select the "Maintenance and Backups" tab to get details on what backups are being taken: That's the basics of what's happening with your backups. However, you can get more detail by choosing the "Automated Backups" page on the left: And now you see all the information about the backups. But the real magic to restore to a point in time is over on…
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