Old Hand was a attentive reader and found the bug :w00t: in Ten Centuries code as follows.

i must say a don't read the cod ereally because i got this constraint violation error many times in the past 😛

declare @myothertab table (

col2 varchar(20),

col3 varchar(20)

)

insert into @myothertab

select 'A','B' union all

SELECT 'W','Q'

;

declare @myanothertab table (

col2 varchar(20),

col3 varchar(20)

)

insert into @myanothertab /* < should be*/

select 'A','B' union all

SELECT 'W','Q';

select 1 as col1, col2, col3 into #mytmp

from @myothertab

insert into #mytmp

select null,col2,col3

from @myanothertab

select * from #mytmp