sql - On a single column : Algebraic operation on Aggregate functions -

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is possible on same sql select query (no function/procedure nor pl/sql) compute algebraic operation on 2 aggregate functions ?

|  id ||   | |-----||-----| |  1  || 10  | |  2  || 20  | |  3  || 30  | |  4  || 40  |   select (select sum(a) table 'id even') - (select sum(a) table 'id odd') table 'condition'

any idea ?

ps : databse oracle 11g

you can this:

select sum(case when mod(id,2)=0 else 0 end) -        sum(case when mod(id,2)=0 0 else end)   test  yourcondition

the sqlfiddle mysql sample, since oracle have mod function should work is.

see working here: http://sqlfiddle.com/#!9/1ba756/2


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