If you run the queries with

SET STATISTICS IO, TIME ON

Is there any difference in the results? If so can you paste them in here?

On thing I've noticed from a very quick look as that the left joins seem to be very similar.

I would look at combining the LEFT JOINS into one query on...

I don't think it should make any difference, as the optimiser will/should work out the best order to execute the joins. So both queries should have the same execution plan...

I don't understand what you want? What sort of ideas are you looking for?

Another question that comes to my mind is the table structure is as below. I am not sure why would it end up having negative values if the identity...

I can't say that I understand your question. What do you mean by: "--ex "t"  has 1,200 , "t1"  1,100 means i want to see 100 to 99 t2 does not...

This will work for all dates between 1800 and 2400, it's more efficient than my previous proposed method

DECLARE @Eff_DateDATE;
DECLARE @Exp_DateDATE;

SET @Eff_Date = '01/01/2020';
SET @Exp_Date = '01/01/2021';

SELECT DATEDIFF(dd,@Eff_Date,@Exp_Date)
...

If you install this table valued function you could do it like this:

DECLARE @Eff_DateDATE;
DECLARE @Exp_DateDATE;

SET @Eff_Date = '01/01/2020';
SET @Exp_Date = '01/01/2021';

SELECT COUNT(Value) AS Days
  FROM...

I submitted a script to truncate tables that have referencing foreign keys. It doesn't do anything with triggers though I'm sure it can fairly easily be amended to do that....

SELECT u.*
  FROM (SELECT DISTINCT fl_group
          FROM Freelancer t) t
 CROSS APPLY(SELECT TOP(2) *
   ...

Have you tried searching the internet for the error "0xC020844B"?

It looks like a timeout.

Yes, good point

;WITH cte AS
(
SELECT * 
  FROM (VALUES (1,'ABD'),
 ...

;WITH cte AS
(
SELECT * 
  FROM (VALUES (1,'ABD'),
               (1,'ACD'),
   ...

John Roberts- Not sure about the errors, I don't get these when I use any of the code I've included. The 2 CREATE TABLE statements and the DELETE all...

Your SQL gives errors:

Msg 1767, Level 16, State 0, Line 42
Foreign key 'FK_ACCT_CHILD_TABLE' references invalid table 'dbo.ACCT'.
Msg 1750, Level 16, State 0, Line 42
Could not create constraint....