ETL

The guiding principle (the motto) Keep UTC for as long as possible. Change to a local timezone only when it is truly required. This principle was not theoretical. It emerged from a real incident — one that almost became a production bug, and only didn’t because of a fortunate configuration coincidence. Why time zones are dangerous in ETL Time-related issues are among the hardest problems in data engineering because: ...

Resumo: Indexes are one of the first performance tools every PostgreSQL user learns — and one of the easiest ways to accidentally slow a system down. This article explains how indexes actually work, why they are never free, how different index types behave in real workloads, and how fillfactor quietly determines whether your database ages gracefully or slowly collapses under write pressure. Indexes Feel Like Magic (At First) You run a query on a table with millions of rows. ...