However, this approach is not generally recommended so we have to find something more appropriate. One option could be forecasting with the Box-Jenkins methodology. In this case, we will use the SARIMA (Seasonal Auto Regressive Integrated Moving Average) model. In this model, we have to find optimal values for seven parameters:
- Auto Regressive Component (p)
- Integration Component (d)
- Moving Average Component (q)
- Seasonal Auto Regressive Component (P)
- Seasonal Integration Component (D)
- Seasonal Moving Average Component (Q)
- Length of Season (s)
To set these parameters properly you need to have knowledge of auto-correlation functions and partial auto-correlation functions.
Read on for a nice overview of this method, as well as the importance of making sure your time series data set is stationary.
In addition to the performance improvements, we’ve also added new functionality to Databricks Delta:
Truncate Table: with Delta you can delete all rows in a table using truncate. It’s important to note we do not support deleting specific partitions. Refer to the documentation for more information: Truncate Table
Alter Table Replace columns: Replace columns in a Databricks Delta table, including changing the comment of a column, and we support reordering of multiple columns. Refer to the documentation for more information: Alter Table
FSCK Repair Table: This command allows you to Remove the file entries from the transaction log of a Databricks Delta table that can no longer be found in the underlying file system. This can happen when these files have been manually deleted. Refer to the documentation for more information: Repair Table
Scaling “Merge” Operations: This release comes with experimental support for larger source tables with “Merge” operations. Please contact support if you would like to try out this feature.
Looks like a nice set of reasons to upgrade.
As this series of articles are published, it will be important that you have a way to do some hands on with Linux, not just read about this powerful operating system. To accomplish this, my recommendation is to download Docker for Windows.
Choosing to use Docker over a VM or a cloud deployment might seem odd at first, but I’ve found that Docker is the perfect option from the testing and classes I’ve led. The Docker image is light–using a minute number of resources on any laptop. Access to the docker image isn’t dependent upon Wi-Fi or the user having a cloud account. The image, for the most part, offers an experience that is incredibly similar to a full Linux server in functionality for no additional cost.
Once you’ve downloaded Docker and have it installed, create a Linux container with SQL Server on your workstation, (thanks to Microsoft) to work with and build your knowledge. Start by opening a Command Prompt, cmd from the search option in Windows.
This post is mostly setup and updating packages. I also want to pitch We Speak Linux if you’re in this boat. Kellyn did our inaugural webinar, too.
As I’ve used SQL Operations Studio more and more, I’ve also been finally using PowerShell in more situations. Given that I like the editor and that there’s a built-in terminal, I’ve been running those in my Ops Studio instance. But for a while I didn’t have a slick way of running an entire PowerShell file in the terminal. Usually, I’d just Ctrl+A/Ctrl+C/Ctrl+V, which is a bit awkward.
But among all the other ways you can customize Ops Studio, you have a lot of control over the key mappings. One way to edit these mappings is to pull up the Command Pallette (Ctrl+Shift+P) and start typing “key”, and you’ll see “Preferences: Open Keyboard Shortcuts”. You’ll also see it mentions the Ctrl+K/Ctrl+S shortcut. This will bring you to the basic Keyboard Shortcuts window, where you’ll need to click “keybindings.json”. Either way, just like Ops Studio’s overall settings (and VSCode’s, for that matter), you get a JSON file you can now tweak. Actually, two of them, with the defaults on the left and your own settings on the right.
Read on to see Jay’s mapping and an explanation of what he’s doing.
First Sign Of Problems: Prefixed Columns
Do you have columns with similar prefixes?
I took the Users and Posts tables from Stack Overflow and mangled them a bit to look like this.
You may not have tables with this explicit arrangement, but it could be implied all over the place.
One great way to tell is to look at your indexes. If certain groups of columns are always indexed together, or if there are lots of missing index requests for certain groups of columns, it may be time to look at splitting them out into different tables.
These things tend to happen, but they can have serious negative consequences for database performance, not to mention the risk of bad data sneaking in.
High Availability (HA) – Keeping your database up 100% of the time with no data loss during common problems. Redundancy at system level, focus on failover, addresses single predictable failure, focus is on technology. SQL Server IaaS would handle this with:
- Always On Failover cluster instances
- Always On Availability Groups (in same Azure region)
- SQL Server data files in Azure
Disaster Recovery (DR) – Protection if major disaster or unusual failure wipes out your database. Use of alternate site, focus on re-establishing services, addresses multiple failures, includes people and processes to execute recovery. Usually includes HA also. SQL Server IaaS would handle this with:
Always On Availability Groups (different Azure regions)
Backup to Azure
Click through for more details.
You mean I can make that upper window useful? Yes. Not only that, but, what ever columns you add to the upper window, your copy of Management Studio remembers what you did. The next time you open this Extended Events session in the the Live Data window, the columns you selected will be there. However, your ability to customize Live Data is even easier than that. If you notice, in the upper part of your SSMS window is the Live Data tool bar. Near the end is a button innocuously titled “Choose Columns.” Click on that and a window similar to this will open:
And you can share the results with others.
Here’s the relevant text in the message box, to facilitate searching:
The storage failed to initialize using the provided parameters. (Microsoft.SqlServer.XEventStorage)
Cannot view the function ‘fn_MSXe_read_event_stream’, because it does not exist or you do not have permission. (Microsoft SQL Server, Error: 15151)
Read on for the solution, and if you’re interested in changing that behavior, vote up the UserVoice submission.