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Oracle database cleanup process after DROP DATABASE command - complete removal checklist

Complete Oracle Database Cleanup Checklist: Remove CDB After DROP DATABASE

Posted on by sanjeeva

Two weeks ago, I dropped a development CDB called TESTCDB on one of our lab servers. The DROP DATABASE command worked perfectly—but that was just the beginning. The server was still littered with configuration files, diagnostic logs, and startup scripts pointing to a database that no longer existed. If you’ve ever run DROP DATABASE INCLUDING Read more about Complete Oracle Database Cleanup Checklist: Remove CDB After DROP DATABASE[…]

ORA-01017 invalid username password error showing Oracle authentication architecture, password hashing versions, and troubleshooting workflow for Oracle 19c/21c databases

ORA-01017: Invalid Username/Password – Complete Guide

Posted on by sanjeeva

Last Updated: December 2025 | Oracle 19c/21c | By Ahaaryo Oracle Version Scope: This guide covers Oracle 19c (fully supported) and Oracle 21c (Innovation Release, already desupported but widely deployed). Introduction “The password is definitely correct!” – Every DBA has said this at least once while troubleshooting ORA-01017 invalid username password. I remember a production Read more about ORA-01017: Invalid Username/Password – Complete Guide[…]

DBA_HIST_ACTIVE_SESS_HISTORY Oracle ASH analysis dashboard showing SQL performance and wait events

DBA_HIST_ACTIVE_SESS_HISTORY: Complete Guide to Oracle ASH Analysis

Posted on by sanjeeva

Introduction Have you ever been asked to explain why your Oracle database was slow last Tuesday at 2:30 PM? Or needed to identify which SQL statements were causing CPU spikes during last night’s batch run? This is where DBA_HIST_ACTIVE_SESS_HISTORY becomes your most powerful diagnostic tool. Recently, we faced a production issue where users reported intermittent Read more about DBA_HIST_ACTIVE_SESS_HISTORY: Complete Guide to Oracle ASH Analysis[…]

Migrating Oracle 19c Database from Local Storage to ASM: A Complete Step-by-Step Guide

Posted on by sanjeeva

Last Updated: December 2025 | Oracle 19c | ASM Grid Infrastructure Have you ever encountered a frustrating situation where your Oracle database is running on local storage, and you need to migrate everything to ASM (Automatic Storage Management) without significant downtime? Recently, we faced this exact scenario with a production Oracle 19c Container Database (CDB) Read more about Migrating Oracle 19c Database from Local Storage to ASM: A Complete Step-by-Step Guide[…]

DBA_HIST_SEG_STAT Oracle database growth analysis dashboard showing segment statistics and capacity trends

DBA_HIST_SEG_STAT: SQL Queries to Track Oracle Growth

Posted on by sanjeeva

Introduction Have you ever needed to analyze Oracle database growth trends but found yourself limited by current snapshot data? In real production environments, tracking database growth trends is a critical aspect of DBA life because this allows businesses not only to foresee the real position in terms of existing hardware but also enables planning future Read more about DBA_HIST_SEG_STAT: SQL Queries to Track Oracle Growth[…]