Posts by Grégory Guillou
In this post I want to cover how to run a DELETE and an INSERT as parts of the same statement. Have a look at the test case I developed.
The Oracle gateway for ODBC provides an almost seamless data integration between Oracle and other RDBMS. I won’t argue about its performance, limits, or relevance. It serves a few purposes; set it up and you’ll be able, for example, to create database links between Oracle and MySQL. This post is intended to share some tips related to the setup of the Oracle Gateway for ODBC with MySQL Connector ODBC on Linux.
You can choose a DBID when you rename your Oracle database. This is probably a bad, unsupported, and useless idea. I assume this hidden feature can help you to mess up all your backups. So my advice would be: “don’t use it.” I performed this test with Oracle 126.96.36.199 on Linux x86. It consists in using dbms_backup_restore instead of nid to rename the database. You’ll find below the few steps require to get to it.
Today I’ve been trying to reproduce in an 11g database one of the problems I faced with 10g—one on those problems Riyaj described in his Multi-Column Correlation and Extended Stats in Oracle 11g post. And the fun part is that I wasn’t able to reproduce it. Yet just setting optimizer_features_enable=’10.2.0.4′ made it show up again. It was as though Oracle can detect Multi-Column Correlation without Extended Statistics. How is this possible? You don’t need any complicated schemas to check this out for yourself; just one table as below….
This 9th post will describe how to remove a node from a 11.1 RAC cluster in silent mode. It will differ from the associated documentation in that it will allow you to remove the node even if it is not available anymore. This procedure has only a few differences from the 10.2 one in the 6th post.
There has been a lot of buzz about the Oracle Exadata Storage Server these past few days. Did you know you can actually estimate the impact of it on some of your queries with SQL Performance Analyzer (SQLPA)? Here is the story.
The process of adding a node to a 11.1 RAC is very similar to the 10.2 process described in Part 5 of this series. For this reason, this post will just focus on what has changed between the 2 versions. Make sure you’ve kept a copy of the voting disk and that you have a backup of the OCR. Check that the locations for all the components to be installed, i.e.: Inventory, Clusterware, ASM, database software, OCR, Voting Disks, and data files, are writable. Confirm that all the prerequisites are met for the node and for the whole cluster with the node to be added.
This seventh post digs into some of the silent installation commands of an 11.1 RAC. As for the Installation of a 10.2 RAC Database, this post shows how to (1) install the 11.1 clusterware, (2) install the 11.1 database, and (3) create a RAC database. It doesn’t explore any Patch Set upgrade since 188.8.131.52 is not out for now. Another interesting question, however, is how to upgrade the 10.2 clusterware to 11.1, since it has to be done in place. So let’s get into it.
This post is for those who think Consistent Gets is the only thing that matters. It’s not. That’s why Statspack and AWR provide not only the top queries sorted by Consistent Gets but also Sorted by IO, CPU, Cluster Waits, and so on. I won’t argue. Check for yourself.
This sixth post describes how to remove a node from a 10.2 RAC cluster in silent mode. It differs from the associated documentation in that it will show how to remove a node, even if it has been made unavailable for any reason, including an error by a DBA or a SA.