How does connection pooling work in ADO.NET?

Updated Apr 28, 2026

Short answer

Connection pooling reuses existing DB connections instead of creating new ones each time.

Deep explanation

ADO.NET maintains a pool of open connections per connection string. When a connection is requested, it is retrieved from the pool, reducing overhead of opening/closing connections.

Real-world example

High-traffic APIs efficiently reuse DB connections.

Common mistakes

  • Changing connection string dynamically causing multiple pools.

Follow-up questions

  • What breaks pooling?
  • How to optimize pooling?

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