As a bit of a sidebar, you may have some people come back with a suggestion of using the built-in STRING_SPLIT() function.  That will seem to work but there...

Have you tried clearing the cache and running the queries again?

DBCC FREEPROCCACHE

You should look at partitioning the table by period.

Can you try this?

It should move the sort to the inserts into the clustered index on the temporary table

DROP TABLE IF EXISTS #temp;

CREATE TABLE #temp
(
  ...

The question is too long for me to read.

If you are inserting with DISTINCT, as you appear to be, that will ensure no duplicates are generated at the source

If you...

I would use an SSMS add-in like ApexSQL Refactor.

There is a free version of it here https://en.freedownloadmanager.org/Windows-PC/ApexSQL-Refactor-FREE.html

I think you only get a trial period with the current version from...

Alternatively using OUTER or CROSS APPLY

SELECT c.CityName, x.MonthName
  FROM dbo.City c
 OUTER APPLY (SELECT TOP(1) m.MonthName
          ...

Try this:

 FROM PROPERTY...

Use CROSS APPLY instead of INNER JOIN

  FROM PROPERTY P 
 INNER Join UNIT U   
    ON P.hMy = U.hProperty
 INNER...

OK, but I still can not figure this out. OR does not work. What I need to find out is to gather data for customers who had invoices before...

I wouldn't write dates as '09/01/2022'

What does it mean? Is it 1st September or 9th January?

Better to write dates in ISO format so for 9th January 2022 write it as...

Wouldn't you add the absolute values?

5% + abs(-5%)  + abs(-3%)

Do you think it's not a good thing? and how do you think like it's a HW work(it's not a HW but I would say type of that).  anyhow...

Now has got the answer he wanted he's deleted the evidence. 🤣

Here you go, this is an answer for your homework lol:

select t1.station_name, count(distinct t2.station_name) reachable_stations
  from train_st t1
  left join train_st t2
   ...