How do I explain stored procedure optimization?

Short explanation:

A stored procedure is database-side code that groups SQL operations and control flow into a callable unit. It can reduce application round trips and centralize data logic, but a procedure can still contain slow queries or hold locks too long. Optimization begins by finding the expensive statements and understanding their plans and transaction behavior.

Key points:

• A stored procedure runs database logic on the database server.

• Inspect plans, rows scanned, loops, indexes and lock waits before changing it.

• Explain one real query change and its measured effect; do not invent timing improvements.

• Compare set-based operations with row-by-row loops where appropriate and verify affected rows and business results after changes.

Interview point:

• Describe the actual SQL-level cause and measurement; “moved logic into a procedure” alone is not proof of improvement.