Lukas Eder hits on an interesting data point:
I’ve found an interesting question on Twitter, recently. Is there any performance impact of using
FILTERin SQL (PostgreSQL, specifically), or is it just syntax sugar for a
CASEexpression in an aggregate function?
Click through for the answer and your daily reminder that SQL variants aren’t pure fourth generation languages—if they were, the optimizer would take all possible constructs of a given desired operation and generate the same execution plan for all of them.