A Fine Slice Of SQL Server
Rob Sewell notes that Azure blob storage container names are case-sensitive:
If you use SQL Backup to URL to backup your databases to Azure blob storage remember that for the container name case is important
Despite all of my Linux love and C-based language tolerance, case sensitivity for filenames and development languages is a relic of a barbaric past. Nevertheless, that’s the minefield we must traverse.
Comments closedThe SQL Server development team was able to remove the PInvoke and PUnInvoke activities during T-SQL execution for many of the spatial methods. A critical aspect of the change is that the change is fully compatible across the server and client scenarios.
The same source code is used to build the managed C++ implementation and the unmanaged C++ implementation. At the risk of understating this work the C++ managed code can be compiled with the C++ /CLI compiler, creating the managed assembly and a few, cleaver templates and macros bridge the native variations allowing C++ native compilation. Any change to the code is made in one source file and built in two different ways.
They also have a couple of demos and point out that if you’re using a spatial index appropriately, the performance benefit from switching to 2016 is upwards of 3x. A 3x performance improvement with no code changes is nothing to sneeze at.
Comments closedRichie Lee shows off Get-TimeSpan and New-TimeSpan:
As is the case with most things, when I find a way for getting something done in a script that is “good enough”, I’ll tend to stick with that method until that method no longer becomes fit for purpose. One such method is printing out the time that something took in PowerShell: many of the scripts on my site use this method to get the duration of a task, and I’ve been using this since PowerShell 1.0
This is certainly an improvement over the old version.
Comments closedDavid Klee discusses an important hypervisor-level metric:
VMware’s CPU Co-Stop metric shows you the amount of time that a parallelized request spends trying to line up the vCPU schedulers for the simultaneous execution of a task on multiple vCPUs. It’s measured in milliseconds spent in the queue per vCPU per polling interval. Higher is bad. Very bad. The operating system is constantly reviewing the running processes, and checking their runtime states. It can detect that a CPU isn’t keeping up with the others, and might actually flag a CPU is actually BAD if it can’t keep up and the difference is too great.
This is extremely useful information for DBAs in virtualized environments. My crude and overly simplistic answer is, don’t over-book vCPUs on hosts running important VMs like your SQL Server instances.
Comments closedReza Rad notes that there’s a new String_Split function in SQL Server 2016:
The new String_Split function is a table function which has two inputs:
String_Split(<main string as input>,<delimiter>)
Usage of it should be within From clause of your query because this is a table function.
I’m curious to see how this compares performance-wise to CLR and tally table split methods.
Comments closedKendra Little discusses having a reusable event logging tool for your database work:
You can’t, and shouldn’t log everything, because logging events can slow you down. And you shouldn’t always log to a database, either– you can keep logs in the application tier as well, no argument here.
But most applications periodically do ‘heavy’ or batch database work. And when those things happen, it can make a lot of sense to log to the database. That’s where this logging comes in.
Bonus points if you feed this kind of logging into Splunk (or your logging analysis tool of choice) and integrate it with application-level logging.
Comments closed