Category: Blog Post
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SystemTap into Oracle
SystemTap into Oracle Topic: This post is about using SystemTap for investigating and troubleshooting Oracle RDBMS. In particular you will learn how to probe Oracle processes and their userspace functions. These techniques aim to be useful as well as fun to learn for those keen into peeking under the hood of the technology and improve
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Indexes in Oracle DB part 2
Indexes in Oracle DB part 2 In my first post about indexes I promised that more in this topic will follow up and here it is… This series of articles is based on observation how developers fail to correctly implement indexing in their applications based on Oracle and aims to provide guidelines on how indexes
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SQLPlotter & my summer at CERN
SQLPlotter & my summer at CERN This summer I got selected for an internship at CERN and it was a summer beyond imagination! I am here to share my wonderful experience with you all and throw some light on the most significant part of this-my project: Developing web-interface for a Physics analysis database, SQLPlotter. In
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Backups in Data Guard environment
Backups in Data Guard environment Physical standby databases seem to be ideal candidates for offloading backups from primary ones. Instead of "wasting" resources (unless you're already using Active Data Guard for example), you could avoid affecting primary performance while backing up your database, especially if your storage is under heavy load even during normal (user-
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GoldenGate Veridata for Data Consistency in WLCG Distributed Database Environment
GoldenGate Veridata for Data Consistency in WLCG Distributed Database Environment Reaching the end of my internship as an Openlab student at CERN, I think it’s appropriate to write a summary of my project in our blog. I will try to give a good overview for the past weeks. Our department provides replication services between CERN
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Scaling up Cardinality Estimates in 12.1.0.2
Scaling up Cardinality Estimates in 12.1.0.2 Topic: Counting the number of distinct values (NDV) for a table column has important applications in the database domain, ranging from query optimization to optimizing reports for large data warehouses. However the legacy SQL method of using SELECT COUNT (DISTINCT <COL>) can be very slow. This is a well
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My experience testing the Oracle In-Memory Column Store
My experience testing the Oracle In-Memory Column Store Oracle patch set 12.0.1.2 has been released and with it comes an important new feature: the In-Memory option. CERN has been involved in the testing of this feature since an early stage so I’d like to take the occasion to share my experience with you! What is
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How to verify if archived log deletion policy is correctly applied?
How to verify if archived log deletion policy is correctly applied? What is the best way to handle archived logs deletion in environments with standby and downstream capture databases? One could use own scripts, to delete for example all backed up archived logs, older than n days. But better way, will be to set RMAN
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Configuring Apache Tomcat datasources
Configuring Apache Tomcat datasources Having the datasource password in my version control systems is an issue that has run after me since the beginning of the time. It is classic that you are always postponing it in the development process untill somebody from the security team comes to your office and tells you “what the
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Java SOAP client with certificate authentication
Java SOAP client with certificate authentication Maybe you are wondering why a java entry in a databases blog? The answer is simple, at CERN, the Infrastucture and Middleware Services section (aka IMS) is part of the Database Services , and, among many other things, we take care of the Java application servers for our users.