SQL Server lets you build temporary tables using the same code as a normal table. These are created using a # sign in front of the table name, #ThisIsTemporary. These only stick around as long as the session they are created in. If you use two ## signs it is created globally and other sessions can see the table with the name specified. These are a great way to help SQL Server do a single workload one time instead of repeatedly. You can run the initial workload and store the results to a temp table; then, you can keep referencing that temp table without repeating that work. These can also help to make complex things more bite-sized and tunable for you, and SQL Server.
