A Fine Slice Of SQL Server
Thomas LeBlanc has a public service announcement:
Microsoft Fabric has been upgrade to a 2.0 runtime for notebooks. This includes updates to the native engine which gives us better performance. More info can be gathered here: Runtime 2.0 in Fabric – Microsoft Fabric | Microsoft Learn
Read on to see what this means for existing notebooks in Microsoft Fabric, as well as what you can do about it.
Leave a CommentThis important feature shows up in a few places. This article discusses its role in Database Projects and in SQL Server Management Studio (SSMS); it defaults to true in both. This simple setting evaluates the delta between your desired schema and your actual schema and calculates if applying your desired schema would result in data loss. If the answer is “yes,” it stops.
An easy example is dropping a table or column. Doing so would clearly lose data. Another, perhaps less obvious, is reducing the range of a column’s data type, like from
INTtoTINYINT, where any existing value under zero or over 255 could be lost. These evaluations are done by the engine whenBlockOnPossibleDataLossis set toTrueand, as a result, you can trust that data in your database is not accidentally destroyed by publishing a schema.
The tricky part becomes dealing with database changes when there will be data loss. For that scenario, I’m not sure the database project approach offers anything significant over writing your own database change scripts.
Leave a CommentAndreas Wolter digs into an environment and builds a report:
Have you ever needed to understand an unfamiliar SQL Server estate quickly? Perhaps you inherited an environment, started working with a new customer, or discovered that the existing server inventory is no longer trustworthy.
In the previous article, Running Get-SqlSafe at Scale Across a SQL Server Estate, I showed how to run Get-SqlSafe across a list of SQL Server instances.
Each report contains a System Overview section. I originally added this section to provide context for the security findings, but it also provides useful estate information such as the SQL Server version, build number, edition, and selected usage indicators.
Click through to see how.
Leave a CommentAndrea Onofri builds a complex chart:
I have often found myself needing to plot a single graph with two y-axes having different scales. For example, this might be useful for representing temperature and rainfall data at a given location. Unfortunately, doing this with
ggplot()is not straightforward.
As Andrea mentions, there are specific circumstances in which having a dual-axis chart is reasonable, and click through to learn how. ggplot2 tends to be rather opinionated regarding visual choice and design. I happen to like those opinions and think they are generally correct, but I can also recognize that there may be exceptions to the rules. For those instances, I think “Somewhat difficult but not impossible” is a solid answer, as it keeps people from doing things inappropriately with a couple of mouse clicks, like setting up those stupid 3D bar charts in Excel. H/T R-Bloggers.
Leave a CommentAmy Esselman provides some guidance:
One of our top tips for explanatory communications is to use color sparingly and purposefully to help your audience understand your data and message. Color should be an explicit choice, not something your software applies by default, whether that’s a graphing tool or an AI assistant generating your first draft. These tools can build a chart in seconds. They might even add highlighting on their own. But they don’t know which data matters most to your audience. That call is still yours. Used thoughtfully, color is often one of the quickest ways to improve a graph.
Color is an extremely powerful pre-attentive attribute, meaning that it’s something we intuitively see and respond to without explicit thought. That’s why choosing what to color can be so powerful. If everything has bright, distracting colors, you lose an avenue to guide the viewer’s eye. But Amy’s example is a good one to show the particular element(s) in the visual that you want people to focus on, and the viewer’s eyes will automatically go there.
Leave a CommentSteve Jones answers a question:
Someone asked why I would use TRY_PARSE after I posted a question at SQL Server Central: Getting the Average. Isn’t is slower?A fair question. This quick post looks at why.
I’d use TRY_CAST() or TRY_CONVERT() in this particular scenario. The main reason I’d use TRY_PARSE() would be if you need .NET-specific parsing functionality, such as parsing dates by a specific locale. The reason is that PARSE() and TRY_PARSE() are an order of magnitude slower than their CAST() and CONVERT() cousins.
That said, Steve’s example reminds me of a PolyBase demo I used to do, in which I took a CSV of North Carolina populations by county and read in the information. In that particular dataset, they would use the letter “A” to describe either “Not enough people to show an answer without potentially violating PII” or “We don’t know what the answer is.” So even though it was clearly a numeric attribute in “Population,” the output process overloaded the definition of that attribute and the only way you would know is to happen to see the three rows in ~1500 that happened to have an A in the column value.
Leave a CommentIn Part 6 of this special Postgres in Production deep dive series, Ryan Booz asks a question that determines how useful
pg_stat_statementscan be for you at all: do you have a high cardinality workload? This episode covers what that actually means, why ORMs, dynamic SQL, and AI-assisted development tools generate more unique queries than you might expect, a side by side demo of the same workload on Postgres 17 and Postgres 18, and the concrete checks that tell you whetherpg_stat_statementsis losing the data you need for query tuning.
Click through for the video and transcript.
Leave a CommentGilbert Quevauvilliers locks things down:
In this blog post, I will show you how to configure OneLake security for a Microsoft Fabric Lakehouse. We will remove the default broad-access role, grant the required Lakehouse access, configure object-, row-, and column-level security, and test the results. The goal is to create a secure-by-default setup in which users can access only the data they need.
Click through for the guide.
Leave a CommentAs with almost everything in SQL Server, there is no one-size-fits-all answer when it comes to temp tables. There are times where temp tables have rescued a query, and others where they’ve just caused trouble. And then there’s the times where you’re just scratching your head.
Can you use a CTE or a derived table in place of a temp table? In many cases, yes! But it doesn’t always work out well. When things get particularly complex, the SQL Server optimizer can struggle to find a good plan that doesn’t involve lots of table scans.
Read on for Andy’s thoughts.
Leave a CommentLouis Davidson shares an approach:
Temp tables fit into my query writing process as one of those last ditch efforts to make a query execute fast enough. Of course it would have been harder if I had followed all the rules and added a lot of test cases, but I had a pretty busy week last week and am finishing this pretty late on Tuesday night, so I just gave my opinions.
I like Louis’s strategy. It’s easy to add a lot of complexity to queries out of habit, to micro-optimize performance, or because of a meandering thought process. But many times, taking a step back to think about what could make a query simpler will be helpful.
One thing I’ll cover that Louis didn’t touch on is that performance level is (or should be) a requirement. If you have a query running millions of times a day on a system, then yes, it makes sense to squeeze out every microsecond. But for an ELT job that finishes in 20 minutes and where you have a 6-hour window to get the data loaded, shaving five minutes off of the query’s runtime isn’t that important, especially if you’re in read-committed snapshot isolation or using another form of optimistic concurrency.
This is why I recommend starting with simple and only moving to more complex solutions when you need them. Now, do I always follow my own advice? Err…well, the sign pointing to Boston doesn’t have to go there itself…
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