SQL Server "fix" query for Hash Match instead of Nested Loops
If you are going to this you should at least use the OPTION ( HASH JOIN ) syntax instead.  Using the LEFT HASH JOIN syntax implicitly enforces the join order.

This is not desirable for hash joins where normally you would expect the smaller of the two tables being joined to be the build input, the top-most table in the execution plan.  Using the option syntax allows the optimizer to decide at run-time which is the best join order.  See these two articles for further reading:

http://blogs.msdn.com/b/craigfr/archive/2006/08/10/687630.aspx

https://msdn.microsoft.com/en-GB/library/ms173815.aspx