Oracle Performance Engineering Guide: AWR, ASH and SQL Monitor in 19c and 23ai

Real Production Troubleshooting with Oracle's Performance Diagnostic Tools

📅 March 02, 2026

👤 Chetan Yadav - Senior Oracle & Cloud DBA

⏱️ 12-14 min read

⏱️ Estimated Reading Time: 12–14 minutes

📊 Master AWR, ASH, and SQL Monitor - The Oracle DBA's Performance Troubleshooting Trinity

Production was slow. Users were complaining. The application team blamed the database. I had 30 minutes to find the root cause before the CTO joined the war room call.

I opened an AWR report. Buffer busy waits: 87% of total wait time. But which sessions? Which objects? AWR doesn't tell you. That's when I switched to ASH. Three sessions hammering the same table block. SQL Monitor showed me the exact query execution plan with real-time wait events. Problem identified: missing index on a foreign key. Index created. Performance restored. Crisis averted.

AWR, ASH, and SQL Monitor are Oracle's three essential performance diagnostic tools. AWR gives you the big picture over time. ASH shows you what's happening right now at the session level. SQL Monitor reveals how individual queries execute in real-time. Together, they form the complete performance troubleshooting toolkit that every Oracle DBA needs to master.

This guide covers real production troubleshooting techniques using AWR, ASH, and SQL Monitor in Oracle 19c and 23ai. If you're tired of guessing at performance problems or spending hours digging through logs, these are the diagnostic queries and analysis patterns that actually work.

Oracle Database 26ai: New Features DBAs Should Test First in 2026

Oracle Database 26ai: New Features DBAs Should Test First

AI-Powered Automation, Vector Search, and Production-Critical Features

📅 February 26, 2026

👤 Chetan Yadav - Senior Oracle & Cloud DBA

⏱️ 12-13 min read

⏱️ Estimated Reading Time: 12–13 minutes

🤖 Oracle 26ai - The Database That Tunes Itself While You Sleep

The Oracle Database 26ai beta went live last week. My manager sent the email: "Download it. Test it. Report back on Monday with what breaks."

I spent 72 hours testing every major feature Oracle advertised. Some lived up to the hype. Others... didn't. Here's what you actually need to test first, based on what will impact production databases most.

Oracle 26ai isn't just another version bump with minor bug fixes. This release introduces AI-driven query optimization, native vector search for machine learning workloads, property graph enhancements, and automated schema evolution. If your organization is considering adopting any of these features, this guide shows you exactly what to test and what production gotchas to watch for.

This isn't marketing hype—it's a DBA's practical testing roadmap based on early access to 26ai. If you're evaluating whether to upgrade, these are the features that matter most and the tests that separate real value from vendor promises.

⏱️ Reading Time: 10–12 minutes

Top-10 Wait Events Query (Universal Database Performance Tuning)

It’s a peak business hour. Users complain the application is “slow,” dashboards look normal, CPU is not maxed out, and storage graphs look fine. Someone asks the classic question:

“The database is up… so why is everything waiting?”

This is the exact moment where strong DBAs look at wait events instead of guessing. Understanding the top-10 wait events is not just a tuning skill —it’s a career-defining mindset.