What are the considerations in performing query optimization?

What are the considerations in performing query optimization? Please provide examples to each consideration

 

use and have a look into these references:

1- this one you 100% have to use:
https://www.pcapps.com/database-services/tuning-and-optimization/sql-server-query-optimization.aspx

o optimize SQL Server queries and increase​ performance, we carefully consider and balance each of the following:"

2- this is a good explanation:

3- this is an example of google.. and the negative/positive considerations for query optimisation at google:

Pros and Cons of Google Advanced Query Operators

4- https://www.1keydata.com/datawarehousing/query-optimization.html

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