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Using wallets with dbca in Oracle 19c

One of the features I haven’t seen blogged about is the option to provide SYS and SYSTEM passwords (among other parameters) to dbca via a wallet. This is documented in chapter 2 of the Database Administration Guide 19c.

[oracle@server1 ~]$ dbca -silent -createDatabase -help
        [-useWalletForDBCredentials  Specify true to load database credentials from wallet]

I was curious how to use this feature as it might provide slightly better security when deploying new databases via dbca. It turned out it wasn’t too hard in the end, and I decided to briefly put my efforts into this short article.

Upgrading…Its Time!

Gough Whitlam was an Australian politician who rose to power in the 1970s with the campaign slogan “It’s Time!”. Politics aside, it loosely ran on the premise that not to have the occasional dramatic change ultimately leads to stagnation in social and economic progress.


Oracle 19c Automatic Indexing: Common Index Creation Trap (Rat Trap)

When I go to a customer site to resolve performance issues, one of the most common issues I encounter is in relation to inefficient SQL. And one of the most common causes for inefficient SQL I encounter is because of deficiencies the default manner by which the index Clustering Factor is calculated. When it comes […]

Video : Hybrid Partitioned Tables in Oracle Database 19c

In today’s video we’ll give a quick demonstration of Hybrid Partitioned Tables, introduced in Oracle Database 19c.

The video is based on this 19c article.

The video only has a single example using external partitions pointing to CSV data. The article also includes and example using a Data Pump file.

Read only partitions

The ability for part of a table to be read-only and other parts of the same table to allow full DML is a cool feature in the Oracle Partitioning option.  Perhaps the most common example you will typically see for this is range-based partitioning on a date/timestamp column.  As data “ages”, setting older partitions to read-only can yield benefits such as:

  • moving the older partitions to cheaper, or write-once storage
  • guaranteeing that older data cannot be tampered with
  • shrinking backup times because read-only data only needs to be backed up once (or twice to be sure)

But if you try this in 18c, you might get a surprise:

Oracle 19c Automatic Indexing: A More Complex Example (How Does The Grass Grow)

In this post I’m going to put together in a slightly more complex SQL example a number of the concepts I’ve covered thus far in relation to the current implementation of Oracle Automatic Indexing. I’ll begin by creating three tables, a larger TABLE1 and two smaller TABLE2 and TABLE3 lookup tables. Each table is created […]

From 19.6 to 19.7 on Windows

I must say this Release Update (RU) was probably the smoothest I’ve ever done. Obviously you should always read the patch notes carefully before proceeding on your own systems, but for me, it was a simple exercise. I’m posting this just to cover a couple of things that the patch notes “assume” and don’t explicitly state.

  • Shutdown everything Oracle related. I just go to “Services” and look for anything with Oracle. Also shutdown the “Distributed Transaction Coordinator service”.

This next one is key … I’ve made this mistake so many times. Open a command prompt window as administrator. If you don’t, things will progress OK for a tiny bit and then OPatch is going to throw a wobbly.

I did both the 19.7 RU and the 19.7 OJVM with OPatch, and both went through without incident.

Copying a SQL Plan Baseline from one database to another

Hopefully this post saves you a few minutes looking the procedure up. I know it’ll save me some time ;) In this rather lengthy article I’d like to cover how I copied a SQL Plan Baseline from one database to another. If you find this procedure useful, please ensure your system is appropriately licensed for it and test it first!

My Setup

My source database is named ORA19NCDB, patched to 19.7.0 running on Oracle Linux 7x/UEK 5. As I do so often, I’m using Dominic Giles’s Swingbench as the source for this experiment. This is the query in question:

Oracle 18c – select from a flat file

By Franck Pachot

This post is the first one from a series of small examples on recent Oracle features. My goal is to present them to people outside of Oracle and relational databases usage, maybe some NoSQL players. And this is why the title is “select from a flat-file” rather than “Inline External Tables”. In my opinion, the names of the features of Oracle Database are invented by the architects and developers, sometimes renamed by Marketing or CTO, and all that is very far from what the users are looking for. In order to understand “Inline External Table” you need to know all the history behind: there were tables, then external tables, and there were queries, and inlined queries, and… But imagine a junior who just wants to query a file, he will never find this feature. He has a file, it is not a table, it is not external, and it is not inline. What is external to him is this SQL language and what we want to show him is that this language can query his file.

Video : Using Podman With Existing Dockerfiles (Oracle Database and ORDS)

Today’s video shows me using some of my existing Docker builds with Podman. Specifically a 19c database container and an Oracle REST Data Services (ORDS) container.

For those with an understanding of Docker, it should look really familiar, but it does introduce a twist in the form of a pod.

The video is based on this article.

You can see more information about containers here.