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I want to optimize my query using short circuit evaluation as below:

Query 1: 

Select emp_id, emp_name 
From emp_table 
Where emp_name = "xyz" 
and emp_id >= 50;

Query 2 : 

Select emp_id, emp_name 
From emp_table 
Where emp_name = "xyz" 
and (emp_id >= 50 or 1 = 0);

Will the addition of or 1 = 0 condition (short circuit evaluation) in query 2 result in optimization?
How exactly would the short circuit evaluation work in above example?

mechanical_meat
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user731503
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1 Answers1

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it won't result in optimization (well,, it could in case there is a bug in the database engine and this would workaround the bug ;)

but i don't thing this question has anything to do with short circuit evaluation - 0 and ?, 1 or ? are short circuit evaluated, not 1 = 0, 0 or ?, 1 and ? nor ? and (? or 1 = 0)

plus the engine should delete or 1 = 0 from your query during compile time (= optimize the query), but i don't know how to inspect the resulting bytecode, so i'm not sure about this...

Aprillion
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