在SQL中加入性能临时表

Question

In my database for somereasons not all table have foreign key then for have a better performance I used a select into (with data filtered) in a temp table , I did this for the tables I'll use for to have a better performance but now....

In the final result when I need do join between those table (temp table can't have foreign key, isn't it?) do not have foreign key I got "Merge Join" (I understand they are caused because my temp table does not have foreign key)

(If you dont see the pic I reupload it at here) https://ibb.co/f0XRHv

Answer 1

How about using something like suggested in the following answer?

No foreign key restraints on a temporary table? SQL Server 2008