Infrastructure at your Service

 
Grégory Steulet

Stop looking for Oracle Fusion and Oracle Grid Control documentation: use the dbi services firefox add-ons!

By | Database management | One Comment

After my last post title “Stop looking for Oracle and MySQL documentation: use the dbi services firefox add-ons!” Some of you asked me for firefox search add-ons for Oracle Fusion Middleware (http://download.oracle.com/docs/cd/E17904_01/index.htm). This add-on will provide you a fast a reliable way to find easily what you are looking for in the official oracle documentation.

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Jérôme Witt

VMware Tools auf Oracle Enterprise Linux 5.6 Guests installieren

By | Hardware & Storage | No Comments

Wenn Sie einen Oracle Datenbank Server auf VMware ESX betreiben, sollten Sie die VMware Tools nicht unterschätzen. Sie sind nicht nur sinnvoll bei Copy-Paste-Aktionen oder für bessere Grafiken, sondern liefern ebenfalls High-Performance-Network, Storage Adapter (PVSCI), Treiber, etc. Auf Linux Guests müssen die Tools mit dem Kernel zusammen kompiliert werden. Besonders auf Oracle Enterprise Linux 5 Upgrade 6 gibt es ein Problem: OEL 5.6 und OEL 6.0 nutzen den neuen Oracle Unbreakable Kernel 2.6.32-100. Wenn Sie…

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Hervé Schweitzer

A SQL statement is slow and suddenly fast? Have a look at “Cardinality Feedback”!

By | Application integration & Middleware | 2 Comments

Discussing with some tuning gourous we were made aware about this feature. It is not so far from the adaptive cursor sharing perfectly described in  Chris’s blog : http://antognini.ch/papers/BindVariablePeeking_20090718.pdf

This feature, compares the real execution (number of returned/actual rows “A-rows”) with some expectations (number of expected rows “E-rows”) and chooses another plan for the next executions if the difference between the expectation and the actual result is too big. “Cardinality Feedback” is not well documented in the Oracle documentation.

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Grégory Steulet

Saving time and increasing service availability with MySQL Enterprise Monitor 2.3

By | Hardware & Storage | 3 Comments

Nowadays MySQL Databases are encapsulated into many mission critical software solutions. Lots of companies host one or many MySQL databases in their data center, sometimes even without knowing it except when the MySQL service is no more available. In order to increase this service availability it is mandatory to have a monitoring solution. Regardles of you are using MySQL Server, MySQL replication or cluster the Oracle/MySQL monitoring solution is called MySQL Enterprise Monitor.

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Grégory Steulet

Stop looking for Oracle and MySQL documentation: use the dbi services firefox add-ons!

By | Database management | 2 Comments

Are you often trying to find some functionalities into ORACLE 10gR2, ORACLE 11gR2 or MySQL documentation ? Of course each time you are looking for this documentation you find unofficial documentation which is never corresponding to the version you are looking for.. we have the solution, three firefox add-ons that will allow you to easily find the right official Oracle or MySQL documentation you are looking for.

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Grégory Steulet

Simulating and testing I/O performances with ORION

By | Application integration & Middleware | One Comment

Since Oracle 11.2, Oracle provides ORION in the RDBMS binaries (in ${ORACLE_HOME}/bin). ORION is an I/O calibration tool allowing to simulating and testing I/O performances an Oracle database would be confronted with.

 

ORION basically supports four kinds of database activities based on either small or large I/O. ORION can, as any respectable I/O simulation tool, generate an adapted workload using a given percentage of reads and write operations.

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Yann Neuhaus

Simulating database-like I/O activity with Flexible I/O

By | Application integration & Middleware | No Comments

You do not want to install or configure swingbench, load runner etc. – just to test the performance of your I/O system based on filesystems? Then Flexible I/O is the right tool for you. This post provides an overview. In order to simulate Oracle database I/O workload on filesystems, ORION cannot be used since it only uses raw or block devices (scratching the filesystem). To simulate Oracle database I/O behaviour on filesystems, we can use…

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Hervé Schweitzer

How to debug a Data Pump error

By | Database management | One Comment

Recently, I had an Oracle error with Data Pump at a Customer, which was not easy to localize. Here is the error I received during a DBIOWNER schema export with Data Pump:

Processing object type SCHEMA_EXPORT/TABLE/STATISTICS/TABLE_STATISTICS
ORA-39125: Worker unexpected fatal error in KUPW$WORKER.UNLOAD_METADATA while calling DBMS_METADATA.FETCH_XML_CLOB [TABLE_STATISTICS]
ORA-00942: table or view does not exist

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