Oracle Exascale supports sparse snapshots and fast cloning at the block level. With Cascade Snapshot Cloning, you can create a clone from another clone: Base PDB → Clone A → Clone B → Clone C This is useful when you need many database copies for development, testing, or migration. In this article, we will lookContinue reading “Understanding Cascade Snapshot Cloning in Oracle Multitenant”
Tag Archives: technology
Exadata Exascale VM Storage is Finally Available
Exadata Exascale VM Storage is officially available in our region! If you are setting up new environments in ExaCC or OCI , Oracle now strongly recommends deploying your VM clusters using an Exascale VM Storage Vault rather than traditional local compute storage. By completely decoupling your VM’s file system from the underlying physical server, thisContinue reading “Exadata Exascale VM Storage is Finally Available”
Ghost in the Datafile: Fixing “Empty Block” Corruption in Oracle
A common frustration for DBAs occurs after identifying a corrupted index or table. You drop the object, expecting the error to vanish, but RMAN backups still fail and Data Guard continues to report a gap. Even though the block is no longer part of a segment, it remains “physically” corrupted in the eyes of theContinue reading “Ghost in the Datafile: Fixing “Empty Block” Corruption in Oracle”
Exadata Snapshot PDB Clone with ACFS
When working with Exadata, there are several ways to create snapshot PDB clones. The main options are: Each one works well, but the best choice really depends on your environment and what you need. Exascale Clone This is clearly the most modern solution. It’s fast, simple, and designed for large environments. But in reality, notContinue reading “Exadata Snapshot PDB Clone with ACFS”
ACFS Replication Background Process Stopped After Upgrade to 23ai
If you recently moved from Oracle 19c to Oracle 23ai, you might find your file replication has stopped. Your status shows “Stopped”, and no matter how many times you try to start it, nothing happens. The Problem: The “SCAN” Name In the old version (19c), replication usually connected directly to a specific server’s name orContinue reading “ACFS Replication Background Process Stopped After Upgrade to 23ai”
Out-of-Place GI Patching Using gridSetup.sh in Oracle 23ai / 26ai
Before performing Out-of-Place Grid Infrastructure (GI) patching, it is strongly recommended to read the following MOS document: Step by Step Out of Place Grid Infrastructure Patching Through gridSetup.sh in Silent Mode(Doc ID 2853839.1) Although this MOS document was written for GI 19.x, it is still largely applicable to Oracle 23ai / 26ai. However, the documentContinue reading “Out-of-Place GI Patching Using gridSetup.sh in Oracle 23ai / 26ai”
Partitioning in PostgreSQL vs Oracle
A customer who had migrated from Oracle to PostgreSQL several years ago recently reported a serious performance regression. A critical table—now holding over 700 million rows—had become extremely slow when filtering by date. As an DBA, I approached this from an Oracle perspective: partition pruning, local indexes. PostgreSQL partitioning is broadly similar to Oracle’s, butContinue reading “Partitioning in PostgreSQL vs Oracle”
When the Clustering Factor Strikes: How a “Perfect” Plan Turned into a 9-Second I/O Nightmare
This wasn’t a theoretical exercise—it was a real-world performance issue that left the database paralyzed.Let’s start with the global stats: The database wasn’t working—it was waiting.Over 90% of the query’s elapsed time was spent on I/O waits, meaning the database was stuck reading data from disk. Step 1: The Execution Plan At first view, theContinue reading “When the Clustering Factor Strikes: How a “Perfect” Plan Turned into a 9-Second I/O Nightmare”
Building a Simple RAG Q&A Assistant with LangChain and OpenAI
I recently explored how to combine LangChain and OpenAI’s GPT models to create an intelligent Retrieval-Augmented Generation (RAG) assistant. This project can read your local documents, store them in a searchable vector database, and answer questions based on your own text . What is RAG? RAG (Retrieval-Augmented Generation) is a powerful technique that combines informationContinue reading “Building a Simple RAG Q&A Assistant with LangChain and OpenAI”
Hello AI, Using OpenAI API with Python
Recently, I tried using OpenAI’s Python library for the first time — and I was amazed at how easy it is to create a conversational AI assistant with just a few lines of code. In this post, I’ll share my experience and a simple Python example that lets you chat directly with GPT right fromContinue reading “Hello AI, Using OpenAI API with Python”
Oracle DBA Insights 