A Fine Slice Of SQL Server
Andrew Pruski tries out a tool:
We’ve all been there as DBAs…people requesting access to the servers that we look after to be able to view certain things.
I’ve always got, well, twitchy with giving access to servers tbh…but what if we could completely restrict what users could do via powershell?
Enter Just Enough Administration. With JEA we can grant remote access via powershell sessions to servers and limit what users can do.
Click through to see how it works.
Comments closedPaul Turley continues a series on working with large amounts of data in Power BI:
You don’t have to have massive tables to benefit from partitioning. Even tables with a few hundred thousand records can benefit from partitioning, to improve data refresh performance and to detect source data changes. There is little maintenance overhead, so the benefits usually outweigh the cost, in terms of effort and management.
Click through for Paul’s thoughts on the topic.
Comments closedSean Gallardy finds the real killer:
If you haven’t already read up on cooperative and preemptive scheduling or aren’t sure what those are, please read the intro to that first, otherwise you’ll be lost.
Much as I’ve discussed before, SQL Server uses a cooperative scheduling model. This doesn’t mean that Windows does, nor does it mean Windows will scheduler whatever SQL Server schedules, in fact much of the time there are many other threads that run before the ones from SQL Server, that’s the job of the operating system to figure out. Due to SQL Server using cooperative scheduling there needs to be a mechanism that exists such that when a resource not under SQL Server’s control needs interaction the scheduler can keep on scheduling and threads can switch in and out (in SQL Server, Windows does what Windows wants). Enter preemptive status and associated waits.
Click through for a deep dive on the topic.
Comments closedMichael J. Swart says don’t worry, be happy:
What’s the best way to avoid most blocking issues in SQL Server? Turn on Read Committed Snapshot Isolation (RCSI). That’s it.
Do check out Erik Darling’s comment as well for one thing to keep in mind if you turn on RCSI.
The other thing to keep in mind is that, if you have WITH(NOLOCK) hanging around everywhere in your code, you won’t get as much of a benefit with RCSI until you remove them.
Abid Nazir Guroo looks at some endpoints:
Azure Synapse Analytics Representational State Transfer (REST) APIs are secure HTTP service endpoints that support creating and managing Azure Synapse resources using Azure Resource Manager and Azure Synapse web endpoints. This article provides instructions on how to setup and use Synapse REST endpoints and describe the Apache Spark Pool operations supported by REST APIs.
Read on to see some of the Spark pool management options are available to you via the REST API.
Comments closedThe role of transformation in Spark is to create a new dataset from an existing one. Lazy transformations are those that are computed only when an action requires a result to be returned to the driver programme.
When we call an action, transformations are executed since they are inherently lazy. Not right away are they carried out. There are two primary types of transformations: map() and filter ().
The outcome RDD is always distinct from the parent RDD after the transformation. It could be smaller (filter, count, distinct, sample, for example), bigger (flatMap(), union(), Cartesian()), or the same size (e.g. map).
Read on to learn more about transformations, including examples of how each works. Even if you’re using the DataFrames API for Spark, it’s still important to understand that transformations are lazy.
Comments closedRobert Cain continues a series on learning KQL:
In the previous article, Fun With KQL – Make_Set and Make_List, we saw how to get a list of items and return them in a JSON array. In this article we’ll see how to break that JSON array into individual rows of data using the
mv-expandoperator.
Read on to learn more about mv-expand.
Bill Fellows runs into an issue:
Perfect, now I have a row for each second from midnight to approximately 5.5 hours later. What if my duration need to vary because I’m going to compute these ranges for a number of different scenarios? I should make that 19565 into a variable and let’s overengineer this by making it a bigint.
Things don’t work out quite the way you might have expected there. Read on and see what Bill found and how you can circumvent the problem.
Comments closedI am often asked about all kinds of various errors, of course with absolutely no context. I also get asked what error X is or means or says… I don’t remember that stuff off the top of my head. The thing is, you kind of need SQL Server to go look it up and there have been a plethora of times when this wasn’t possible. I’ve also noticed that people tend to give you just the error number and not anything else.
Read on to learn more about what Sean has created, akin to the SQLskills wait stats compendium.
Comments closed