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  • Dustin Waybright thinks this is interesting:

it is important not to draw any performance-related conclusions from what you learn about logical query processing. That’s because logical query processing only defines the correctness of the query.

From

Cover of Training Kit (Exam 70-461): Querying Microsoft® SQL Server® 2012

Note

Optimization is done by the database engine, as T-SQL is not an imperative language where you instruct how to execute steps. You only instruct on what you want to obtain.