A few months ago, I struggled with a planning system. I needed to ensure that no 2 plans could overlap for the same period. My first instinct was to write application-level validation, but something felt off. I thought to myself that surely PostgreSQL had a better way.
Turns out, PostgreSQL is packed with a bunch of underrated (and often simply overlooked) features that can save you from writing complex application logic:
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EXCLUDEconstraints: To avoid overlapping time slots -
CHECKconstraints: For validating data at the source -
GENERATEDcolumns: To let the database do the math -
DISTINCT ON: Cleaner than aGROUP BYwith subqueries -
FILTER: To add a condition directly on the aggregate
Even after years of using it, I still discover features that make me question why I ever wrote complex application logic for things the database could handle natively.
I wrote an even more detailed version with examples (in case anyone thinks this isn’t long enough lol)
Are there any other advanced PostgreSQL features I should know about?
DISTINCT ON is not an aggregate like group by; it allows you to select the first row matching the distinct clause given the ordering. It IS super useful!


