Wednesday, July 31, 2013
Why so fond of UNION?
I'm wearing my sargchitect hat in our current sprint. Aside from improving the speed of the existing queries by making them sargable and devoid of unintended cartesian-yielding joins, the optimization team need to make sure the queries are properly refactored, easy to maintain, smooth and suave to the eyes, so the developers could have a pleasant time reading and understanding the queries.
I saw some UNION queries that can be made simpler using OR. I don't think it's ok to have a union of the same table, union like that tend to be DRY-violating, tend to have many lines, hence harder to debug and harder to optimize
I'm thinking, why the inordinate fondness for UNION if the query can be made simpler with OR? Last I checked, Microsoft haven't disabled the OR functionality. So let's rejoice to the fact that Microsoft don't have any plans to disable OR functionality for the foreseeable future.
Happy Sarging! Scratch that, Happy SARGing! ツ