Each number you test for primality needs O(sqrt(n)*n) calculations, so it will slow down for larger numbers. Also, if you increase @n to 10 times its previous value each...

You only need to test up to the square root of a number to test for primality, which is quite a saving:

declare @n   ...

Oh you're right.  This is not the final version but I'm not finding my notes on this.   Iirc if you follow the links it leads to a SQLlite script with...

For exhaustive methods it's quicker to only look at odd numbers.  There was a Youtube video a little while ago where they compared all different programming languages to determine which...

Ok thanks.  Yeah maybe I misread this one.  When there are spaces in object labels it causes flashbacks to a difficult job

Is the QUOTENAME to make the sample data?  🙂

Looking at the first picture above the ordering of the Hours doesn't seem clear.  Is it ASCENDING by [Run Start Time]?  In the output, when the System value equals 6,...

Why settle a tie using query logic, what about a unique index?  Some or one of those could be helpful.  A table containing holidays to exclude could be useful too. ...

Doh, well I'd like to edit my edit in the previous post.  Instead of "Removed IN from WHERE clause" it should say "Removed IN from WHEN condition" or something like...

Maybe add a boolean column to the partition

select *, v.grp,
       [test33] = case when v.grp=1 
     ...

• This reply was modified 1 year, 6 months ago by  Steve Collins. Reason: Removed IN from WHERE clause

Thanks to ChatGPT for creating the temp table

DROP TABLE if exists #TempTable;
go
CREATE TABLE #TempTable
(
    ID INT,
    flag int,
   ...

For the first query ChatGPT-4 generated

WITH CompanyAverageRent AS (
    SELECT c.CompanyId, AVG(p.Rent) AS AverageRent
    FROM #Companies c
    JOIN...

What happens if/when there are gaps in the CreatedDate column for particular CustomerID's?

additional JOIN's and CROSS APPLY's apply to the rectangle defined immediately above it (in order of appearance) within the FROM clause

Thinking inside rectangles is how I...