Recently I wanted to create a policy managed database in my flex cluster setup, but free servers are not available. Hence I had to unregister an administrator managed RAC database (amdbh12) to make the servers available. Having completed my testing, I dropped the policy managed database and then wanted to drop the database amdbh12 using DBCA. It was then… Continue Reading →

All Things Oracle Full Articles

In this fifth article in our series on JSON and the Oracle database we’ll be pulling the curtains back on the magic tricks that can convert your boring old relational data to JSON. OK, maybe that’s overselling it a little. Obviously there’s no magic involved; indeed some may say it’s anything but. But before we get to all of that,… Continue Reading →

All Things Oracle Full Articles

Oracle In-Memory is fully compatible with Oracle multitenant database architecture, allowing us to take advantage of fast In-Memory and low-cost storage. This multitenant architecture was also introduced in Oracle 12c, featuring multiple pluggable databases (PDBs) within a container database (CDB). This makes it easy to consolidate databases onto the cloud, deliver a high density of schema-based consolidation without making changes… Continue Reading →

All Things Oracle Full Articles

Hacking Indexes

Jonathan Lewis on 03 October 2016 with 3 comments

Indexes are expensive to maintain so we want to get the greatest benefit we can from them and make sure that Oracle uses them whenever it’s appropriate. Sometimes, though, the optimizer seems to ignore indexes that we think would be very effective and when this happens it’s often because the statistics that Oracle has gathered do not reflect the quality… Continue Reading →

All Things Oracle Full Articles, Performance Tuning, Troubleshooting

There’s a possibility you’ve parachuted into this series on JSON and Oracle at this point. If you are already familiar with what JSON is and how it is created, and are only interested in discovering how to wrestle JSON data from an Oracle database, then you’re welcome, grab a seat. However, if you see the words JSON and Oracle, and… Continue Reading →

All Things Oracle Full Articles, Database Development

Introduction Oracle Database 10g Release 1 introduced Automatic Storage Management (ASM), a new framework for managing Oracle database files. ASM provides a foundation for highly efficient storage management with direct I/O, redundancy, striping and load balancing. Files stored on ASM are evenly distributed across disks in a disk group and mirrored according to the policies defined in the disk group…. Continue Reading →

10g, 11g, 12c, All Things Oracle Full Articles

Rebuilding indexes is an activity that you shouldn’t need to do often. There are always a few special cases – like when you’ve moved or recreated a table or if you’ve done a massive delete on a table – when it’s probably a reasonable idea but, in general, there are very few cases where there’s any great benefit to be… Continue Reading →

All Things Oracle Full Articles, Oracle Database, Troubleshooting

The Oracle Database In-Memory option was introduced in Oracle 12c ( patch set). By using the In-Memory option, businesses can benefit from better decisions made in real time, improved productivity, increased competitiveness and lowered costs. The Oracle In-Memory option is designed to fit both Data warehouse and mixed workload OLTP databases, and can be deployed with any existing application that… Continue Reading →

12c, All Things Oracle Full Articles

Cloning of a Pluggable Database (PDB) in Oracle Multitenant is a great feature and is very useful. Oracle Database 12c Release 1 has introduced various enhancements to the cloning of Pluggable Databases to overcome the limitations imposed by the initial release of Oracle Database 12c ( In Oracle PDBs can be hot cloned, i.e. you don’t need to put the source PDB… Continue Reading →

12c, All Things Oracle Full Articles

Welcome to part three in this series of articles about Oracle and its uneasy romance with JSON. Uneasy? Well, that’s a bit of a spoiler; so far it’s been smooth sailing. Part 1 was a precis of JSON, while Part 2 delved into the reasons for Oracle’s involvement in the area. So far so good; but now we’ve got to… Continue Reading →

All Things Oracle Full Articles