Database Administration & Monitoring

By Franck Pachot

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Oracle Enterprise Linux (OEL) is a Linux distribution which is binary compatible with Red Hat Enterprise Linux (RHEL). However, unlike RHEL, OEL is open source, free to download, free to use, free to distribute, free to update and gets free bug fixes. And there are more frequent updates in OEL than in CentOS, the free base of RHEL. You can pay a subscription for additional support and features (like Ksplice or Dtrace) in OEL. It can run the same kernel as RHEL but also provides, still for free, the ‘unbreakable kernel’ (UEK) which is still compatible with RHEL but enhanced with optimizations, recommended especially when running Oracle products.

By Franck Pachot

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I had a few questions about the Oracle ACE program recently and I thought about putting some answers there. Of course, that’s only my point of view, there’s an official web page: https://www.oracle.com/technetwork/community/oracle-ace/index.html

The program is flexible and open, with a large diversity of people, technologies, contributions, levels,… Then rather than explaining what it is, which would be limiting, I’ll rather tell you… what it is not.

By Franck Pachot

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We have an incredible number of possibilities with Oracle. Yes, an index can be global (indexing many partitions without having to be partitioned itself on the same key) and partial (skipping some of the table partitions where we don’t need indexing). In the previous post of this series of small examples on recent features I partitioned a table, with covid-19 cases per day and per country, partitioned on range of date by interval. The index on the country code (GEOID) was not very efficient for data ingested per day, because countries are scattered through all the table. And then I have reorganized the old partitions to cluster them on countries.

My global index on country code is defined as:

By Franck Pachot

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In this series of small examples on recent features, I have imported in a previous post, the statistics of covid-19 per day and per countries. This is typical of data that comes as a time-series ordered by date, because this is how it is generated day after day, but where you probably want to query from another dimension, like per countries.

By Franck Pachot

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This post is part of a series of small examples of recent features. I’m running this in the Oracle 20c preview in the Oracle Cloud. I’ll show a very basic example of “Row Pattern Recognition” (the MATCH_RECOGNIZE clause in a SELECT which is documented as “row pattern matching in native SQL” feature by Oracle”). You may be afraid of those names. Of course, because SQL is a declarative language there is a small learning curve to get beyond this abstraction. Understanding procedurally how it works may help. But when you understand the declarative nature it is really powerful. This post is there to start simple on a simple table with time series where I just want to detect peaks (the points where the value goes up and then down).

By Franck Pachot

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After reading the https://cloudwars.co/oracle/oracle-deal-8×8-larry-ellison-picks-amazons-pocket-again/ paper, I am writing some thoughts about how a database can be serverless and elastic. Of course, a database needs a server to process its data. Serverless doesn’t mean that there are no servers.

By Franck Pachot

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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.

By Franck Pachot

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This post is part of a series of small examples of recent features. I’m running this in the Oracle 20c preview in the Oracle Cloud. I have created a few tables in the previous post with a mini-snowflake scheme: a fact table CASES with the covid-19 cases per country and day. And a dimension hierarchy for the country with COUNTRIES and CONTINENTS tables.

By Franck Pachot

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In a previous post I introduced Tibero as The most compatible alternative to Oracle Database. Compatibility is one thing but one day you will want to compare the performance. I’ll not do any benchmark here but show you how you we can look at the performance with TPR – the Tibero Performance Repository – as an equivalent of AWR – the Oracle Automatic Workload Repository. And, as I needed to run some workload, I attempted to run something that has been written with Oracle Database in mind: the Kevin Closson SLOB – Silly Little Oracle Benchmark. The challenge is to make it run on Tibero and get a TPR report.

SLOB

I’ve downloaded SLOB from:

By Franck Pachot

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There are good reasons for NoSQL and semi-structured databases. And there are also many mistakes and myths. If people move from RDBMS to NoSQL because of wrong reasons, they will have a bad experience and this finally deserves NoSQL reputation. Those myths were settled by some database newbies who didn’t learn SQL and relational databases. And, rather than learning the basics of data modeling, and capabilities of SQL for data sets processing, they thought they had invented the next generation of persistence… when they actually came back to what was there before the invention of RDBMS: a hierarchical semi-structured data model. And now encountering the same problem that the relational database solved 40 years ago. This blog post is about one of those myths.