Oracle - Trouble Shooting & performance monitor by OEM

The goals of Oracle troubleshooting include:

• Learn a troubleshooting methodology for use in analyzing any Oracle database
• Understand ratio-based and bottleneck troubleshooting analysis
• Learn troubleshooting techniques for monitoring and optimizing memory usage
• Know how to quickly pinpoint and resolve I/O hotspots at the database, storage and object level
• Using scripts to uncover session-related bottlenecks
• Understand techniques for locating and fixing problem SQL

Oracle Stored Procedures Tips

-- prototype defines the syntax for compiling or decompiling a procedure.
Alter procedure <procedure_name> compile | decompile;

Monitor oracle performance by OEM

Proactive Database Tuning

Reactive Database Tuning

SQL Tuning

Resources: https://docs.oracle.com/cd/B28359_01/server.111/b28275/toc.htm