Programming Tutorials

  You have just launched a feature. Traffic is spiking, users are signing up, and suddenly your application crashes. Checking your Vercel or server logs reveals a critical database error: FATAL: remaining connection slots are reserved for non-replication superuser connections Or perhaps simply:  FATAL: sorry, too many clients already . This is the classic "Serverless vs. SQL" bottleneck. If you are running a Next.js application (or any serverless architecture) connected to a standard PostgreSQL instance on Supabase, this error indicates you have exhausted your database's connection capacity. Here is why this happens, why upgrading your instance isn't the immediate answer, and how to implement the technical fix using Connection Pooling. The Root Cause: Serverless vs. Stateful Connections To solve this, you must understand the architecture gap between your application and your database. PostgreSQL was designed for long-running, persistent connections (stateful). When a ...