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Database

Everything our consultants learn while running databases for customers: Oracle, PostgreSQL, SQL Server, MySQL, MariaDB, MongoDB and Delphix. Expect hands-on posts about installation, day-to-day administration, backup and recovery, performance tuning, replication and upgrades.

Automatic column formatting in Oracle sqlplus

Column formatting was always a pain in sqlplus when writing queries on the prompt. Most people use tools like SQL Developer or Quest TOAD which can scroll horizontally when running queries against a database, but as a consultant you are often still forced to use sqlplus. Here’s the issue: When running e.g. a query on a table T1 (which is… 

Getting started with Exasol – Sessions and auditing

This is the fourth post in the series about Exasol and this time it is about sessions and auditing. If you are interested in the previous posts you can find them here: Getting started with Exasol – Setting up an environment Getting started with Exasol – Loading data from PostgreSQL Getting started with Exasol – Some words about indexes and… 

Getting started with Exasol – Some words about indexes and transactions

If you followed Getting started with Exasol – Setting up an environment and Getting started with Exasol – Loading data from PostgreSQL you should have an Exasol test system up and running and a virtual schema pointing to a PostgreSQL schema. What we’ll be doing in this post is to load the data from PostgreSQL into Exasol and then have… 

Oracle ADB from a Jupyter Notebook

By Franck Pachot . My first attempt to connect to an Oracle database from a Jupyter Notebook on Google Colab was about one year ago: https://medium.com/@FranckPachot/a-jupyter-notebook-on-google-collab-to-connect-to-the-oracle-cloud-atp-5e88b12282b0 I’m currently preparing a notebook as a handout from my coming SQL101 presentation where I start with some NoSQL to discover the benefits of RDBMS and SQL. I’m running everything on the Oracle Database… 

Getting started with Exasol – Loading data from PostgreSQL

In the first post of this series we brought up an Exasol test system to have something to play with. Because playing without data is a bit boring this post is about loading data from PostgreSQL to Exasol. We’ll use pgbench on the PostgreSQL side to generate some data and then load that into Exasol. Exasol comes with a concept… 

Getting started with Exasol – Setting up an environment

Exasol is an in memory database with parallel processing, or shorter MPP(Massively Parallel Processing) database. I got in touch with some people from Exasol at the DOAG 2019 in Nuremberg but never had the time to take a closer look since then. Over the past few weeks however I finally had the chance to get in touch with the system… 

Oracle MAA reference architecture and HA, DR, RTO, RPO

By Franck Pachot . I may have mentioned in some previous blog post that, in my opinion, the names of Oracle Database features make sense on the vendor product management context more than in a user context. I’m not saying that it is good or bad. There are so many features, that can be combined, and that evolved for many… 

ODA appliance creation error and cleanup.pl with option force

I had recently faced an interesting issue deploying ODA X8-2-HA. I would like to share my experience here hoping it could help some of you. Error in creating the appliance After reimaging both node0 and node1 from the ODA X8-2-HA, running the configure-firstnet and updating the repository I was going to create the appliance. On ODA X8-2-HA the appliance creation… 

How to migrate High Availability databases on an ODA?

Through this blog, I would like to show, with a real customer case, how I have been migrating databases in High Availability environment on an ODA. High Availability using Data Guard for Oracle Enterprise Edition or dbvisit for Oracle Standard Edition 2. One of the advantage here would be to use the Standby Database as fallback in case there would… 

How to synchronize the appliance registry metadata on an ODA?

Databases administration on a Bare Metal ODA will be done as root user by running odacli commands : odacli create-database to create a database odacli upgrade-database to upgrade a database between major releases odacli move-database to move databases from one Oracle home to another of the same database version odacli update-dbhome to update a specific RDBMS home to the latest… 

Azure Database for PostgreSQL

This Blog is about some findings on Microsoft’s Azure service for PostgreSQL which I think needed to be noted. Findings about the infrastructure The Microsoft Azure Service for PostgreSQL is using Windows as OS Infrastructure, there are several points where it is possible to find out the used OS on PostgreSQL Level. select version(); => PostgreSQL 11.6, compiled by Visual… 

Oracle DML (DELETE) and the Index Clustering Factor

As a consultant working for customers, I’m often in the situation that I have an answer to a problem, but the recommended solution cannot be implemented due to some restrictions. E.g. the recommendation would be to adjust the code, but that is not feasible. In such cases you are forced to try to help without code changes. Recently I was…