SQL Server 2019

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/* 
  ok, someone sent me to this db<>fiddle page, now what?
  
  The purpose of this is to make it easy for people to 
  understand your schema and data so they don't have to
  spend time figuring that out, and can instead focus
  on your issue.
  
  So put some create tables etc. here:
*/

CREATE TABLE dbo.whatever(col date);
  
/*
  And some sample data, including edge cases:
*/

INSERT dbo.whatever(col) VALUES(getdate());
1 rows affected

/* and then the query you're struggling with */
/* and maybe some sample desired results */
/* for more info: https://sqlblog.org/ask */