Press "Enter" to skip to content

Day: January 15, 2024

Sample Data in Azure ML Designer

Published 2024-01-15 by Kevin Feasel

Tom LaRock shows us where the hidden data is:

Recently I was working inside of Azure ML Studio and wanted to browse the sample datasets provided. Except I could not find them. I *knew* they existed, having used them previously, but could not remember if that was in the original ML Studio (classic) or not.

After some trial and error, I found them and decided to write this post in case anyone else is wondering where to find the sample datasets. You’re welcome, future Tom!

Click through to see where those sample datasets are. And yeah, they don’t get updated that frequently. And that’s probably a good thing, as it means when you run the demo two years after someone created it, you’ll still get predictable results.

Comments closed

T-SQL Tuesday 170 Roundup

Published 2024-01-15 by Kevin Feasel

Reitse Eskens writes up a roundup about abandoned projects:

When I thought of this subject last year, I was really on the fence if it would work or not. Part of me was convinced it would elicit some response from the community, part of me was convinced people would be looking for a ‘happy’ start of the year and might not want to think or write about past learnings.

Part of me was right, but I never expected SO MANY of you to jump in and write so many wonderful blogs. It feels a bit unfair to summarise all your hard hard work, so please click the links to read the full stories. Well worth your time!

Click through for plenty of stories on the topic of lessons learned from abandoned projects.

Comments closed

Cross-Database Sync in Azure SQL Database

Published 2024-01-15 by Kevin Feasel

Jose Manuel Jurado Diaz goes through a lot of work to replicate replication:

This week, we addressed a service request from a customer who wanted to keep two tables synchronized across different databases on the same Azure SQL Database server. Unfortunately, in Azure SQL Database, it’s not possible to directly call the database in the operation, for instance using the command select * from master.sys.sys_databases. For this reason, I’d like to share an alternative to tackle this limitation.

This is a way to do it, and it’s fine if there’s only one entry point for the data and you’re okay with writes taking more than twice as long. But this is a perfect use case for transactional replication. The only problem is, Azure SQL Database doesn’t support being a transactional replication publisher or distributor, only a (push) subscriber.

Comments closed

The Power of Schema Binding

Published 2024-01-15 by Kevin Feasel

Guy Glantser explains what schema binding is and why it’s important:

In SQL Server, when we use the “WITH SCHEMABINDING” clause in the definition of an object (view or function), we bind the object to the schema of all the underlying tables and views. This means that the underlying tables and views cannot be modified in a way that would affect the definition of the schema-bound object. It also means that the underlying objects cannot be dropped. We can still modify those tables or views, as long as we don’t affect the definition of the schema-bound object (view or function).

At one point, I was a lot more gung-ho about schema binding and would do it even for views that didn’t require it, as I liked the idea of protecting the schema from changing. This turned out to be more of an annoyance than a benefit, though, so I quietly modified that belief a while ago. Nowadays, I’ll typically use schema binding when it’s required and on the rare occasion in which I create a function (assuming the function complies).

Comments closed

Fixing Key Lookups

Published 2024-01-15 by Kevin Feasel

Erik Darling has some advice:

Key lookups represent a choice made by the optimizer between:

  • Clustered index scan
  • Nonclustered index seek/scan + Clustered index lookup

Lookups can be quite useful to avoid creating quite wide nonclustered index, but the optimizer is heavily biased against them. It does not like random I/O.

Read on for Erik’s thoughts on the matter and how you may be able to improve the performance of a query by removing a key lookup—or sometimes, how you may safely ignore a key lookup because hey, it’s a 1 millisecond difference on a query that runs once a day.

Comments closed

Blocking and Waiting in Power BI Import Mode Refreshes

Published 2024-01-15 by Kevin Feasel

Chris Webb has some ‘splainin to do:

Following on from my previous post showing how you can visualise the job graph for a Power BI Import mode semantic model refresh, I this post I will look at how you can interpret what the job graph tells you – specifically, explaining the concepts of blocking and waiting. As always, simple examples are the best way of doing this.

Click through for the explanation using a job graph.

Comments closed