I'd be checking your maintenance schedules.  Things like statistics updates, index rebuilds, index reorganizations, etc.  Or an absolute worst case - flushing any caches.

Since the problem happens around the same...

I personally don't use R or Python in SQL Server, but my understanding is that both of these have great analytics and graphing libraries in them.

Do you have some sample data where there are duplicates?  With the sample data you provided, the results appear identical to what you had in the screenshot.

If I know some...

Unfortunately, the only reply I see is Phil's latest one.  The one before that was flagged as SPAM.

But Phil is well known on this forum, so I doubt his reply...

As far as I know, there is no magic number to say more than x indexes will impact performance.  Having 1 index may impact performance, 2 might, or 100 might...

I agree with Thom.  I want to add another point that MIGHT be a cause for slowness - memory.  If the package is a simple data flow task that just...

Can you post the relevant logs or portions of the logs?  My expectation is that the logs will give us (and you) a better idea as to what is happening...

Looking at your tables, do you have any keys on them?  If so, then it is pretty easy to do.  If you have no keys on it, then it is...

As a thought - do you have SSRS 2017 installed on that computer already?  If memory serves, you cannot have multiple SSRS's installed on a single instance with newer versions...

Steve - I'd like to touch on your point of:

support UGs (physical and virtual) -  I don't know what goes on here, but I'd like to know. Really, I question...

I agree with Phil here.  100%.  More than 100% if that was possible!

Originally we had a lot of "one-off" SSIS packages that were created for moving data for a very...

1 - An opportunity to meet and learn from experts in SQL and learn about new features in the Microsoft data platform

2 - An opportunity to talk to other data...

As a former UG leader and a speaker, I ran the user group more because it was fun to learn and meet other speakers.  Getting free admission to PASS was...

Powershell and visual basic script.

You also say "C# NET", but really any .NET language (or even non-.NET languages like VB6) can talk to SQL Server.

It really depends on what you...

Technically, you could even bump that down to 1 trigger instead of 2 by having it as a for update AND insert.  Doing it as 1 trigger might not help...