All Things Oracle Full Articles

Oracle for Absolute Beginners: Users, Synonyms, Privileges, & Roles

I accidentally locked myself out of my house this evening, and so I had to climb up the wall like a burglar and clamber in through a bathroom window, while the neighbourhood kids all watched and giggled, probably taking secret photos to share on Snapchat or something.  Embarrassing, yes, but what’s it got to do with Oracle? Well, the point… Continue Reading →

Getting started with Oracle Database 12c Multitenant Architecture

Oracle database, since its inception, has always used a very specific and unique architecture which served it very well. In earlier forms of this architecture, all components of the database were meant to work in a one-to-one mapping with each other. But from version 12c onwards, a completely new architecture has been introduced – Oracle Multitenant. In other words, from… Continue Reading →

JSON For Absolute Beginners: Part 6 – Generating JSON post-12c Release 2

In this sixth and final installment in this introductory series on JSON I’d like to revisit the question of generating JSON from your Oracle database. Cos it’s great to be able to consume a format; but if you can’t spit it out easily too you’ll probably want to look elsewhere. Easily, that’s the keyword in that sentence. In my previous… Continue Reading →

Oracle for Absolute Beginners: Data Types

All databases stand on a tripod of datatypes: strings, numbers and dates. And so I’d imagine that by Day 2 or so of dabbling with Oracle you’d be starting to get reasonably comfortable with the VARCHAR2, NUMBER and TIMESTAMP data types. And that’s a good thing, familiarity with those three data types will take you a long way into a… Continue Reading →

Oracle Partitioned Index Efficiency

PartitionedIndexEfficiency Although it is generally true that rebuilding an index represents a waste of time and resources, there nevertheless exist situations where degenerated indexes might benefit from reorganisation. When you think you are in such a situation, instead of shooting in the dark and rebuilding all indexes, you are better off finding and rebuilding only those indexes occupying more space… Continue Reading →

Policy-Managed Oracle RAC One Node Databases

Oracle RAC One Node, introduced in Oracle Database 11g Release 2 (, is a single instance of an Oracle RAC-enabled database running on one node in a cluster. It lets you consolidate multiple databases onto a single cluster while providing high availability benefits of failover protection to the single instance databases. Oracle RAC One Node databases can be configured to… Continue Reading →

Oracle for Absolute Beginners: Date, Timestamp and Interval

All databases stand on a tripod of datatypes: strings, numbers and dates. And though they might dress them in fancy clothing – varchar2, clob, float, integer – strings are really just strings, and numbers are really just numbers. But dates — dates are interesting. In this article I’ll talk to you about dates, about time, and about how both are… Continue Reading →

Oracle for Absolute Beginners: Other SQL Functions

Here’s a simple trick you can play on your friends. Ask them to pick a number from 1 to 10, and tell them you’ll read their mind and magically extract from it the number they’ve chosen. Don’t give them too long to choose; then put on your best imitation of a magician and say… 7. I don’t know why, but… Continue Reading →

Duplicate Point-In-Time Recovered PDB Using Backup

At times, we might need to duplicate a production pluggable database to a Past Point in Time without disturbing the production database itself, in order to: View the data in the Production Database (PDB) as it appeared then Perform testing Generate reports, etc. Duplication of a PDB slightly differs from that of a non-CDB. In order to duplicate the PDB, an… Continue Reading →

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