RDBMS Server

Oracle RDBMS Server Articles



Written JP Vijaykumar
Date Jan 4th 2020
Modified Jan 5th 2020
This article/script is provided for educational purpose ONLY.
The readers are advised to make necessary changes to the script as may be required for their use in their respective environments.
Pls test these scripts thoroughly in a lower environment, ONLY if you are satisfied with the tests' results, then ONLY use in any

How to move a table from one schema to another


Many times I've seen the question on forums "How can I move a table from one schema to another?" and the answer is always that you can't. You have to copy it. Or export/import it. Well, here's a way. It assumes that you are on release 12.x and have the partitioning option.

19c Standard Edition permits 3 PDBs per CDB


A very nice licensing change in 19c: you can now have up to three PDBs in a Standard Edition Multitenant database.

Compression test, 12cR2


Just how effective is Hybrid Columnar Compression? This test shows that HCC is impressive, but that thought needs to be put into choice of compression algorithm.

12cR2 lots of new instance parameters


Comparing database 12cR1 release to 12cR2 release, I see these new parameters:

12cR2 new feature: online table move


Move a table without locks and without breaking indexes. That's pretty cool.

How indexes can degrade performance


Indexes may improve the performance of SELECT statements, but what about DML? This simple demo shows how bad they can be.

Partitioning and Oracle Standard Edition


I first came across partitioning with release 7, when it didn't exist. Like many DBAs, I simulated it by writing a lot of application code. You can still do this – and you may have to if you haven't bought Enterprise Edition plus the partitioning option. Here's another way to do it, with partitioned views.

When is an index access path better than a full table scan?


The cost based optimizer makes decisions that can be hard to understand. One of the hardest may be why it chooses indexed or scan access paths: a burning question for many DBAs.


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