This article tells you how to create raw partitions in Solaris 10, installed using VMware. The raw partitions can be used later, for configuring ASM instance diskgroups. I am assuming that those who read this article, have installed/know how to install, Unix on a VMWare setup.
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In a recent case, a user was unable to fetch any data with a filter, even though data existed for that value. We did a study,
and came up with this test case of data type mismatch
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Oradebug is a powerful utility provided by Oracle. This tool is normally used on directions from Oracle support as its contents are mostly undocumented. However, many documents by third parties are readily available on the internet.

This tool should be used with utmost care and understanding. We will restrict our discussion about this tool to tracing, and will cover other features some other day!
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Oracle’s dbms_system package can be used to manipulate other user sessions, trace sessions and other purposes. The DBMS_SYSTEM package is well known, but it’s an undocumented package. You won’t find references to it in the manuals. Oracle doesn’t support the use of this package, and you use it at your own risk.
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The dbms_support is an undocumented package and is generally used only on intstructions from Oracle Support. The main purpose of this package is to trace user sessions and provide more information (waits and binds) than is generally available by the SQL_TRACE method.
The trace file is located in the directory mentioned in the user_dump_dest parameter.

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Starting with Oracle 10g, Oracle has introduced a package called DBMS_MONITOR. This package provides flexibility to trace using identifiers,
like client, session, service, module or action. You could also enable tracing at an instance level using the package.Unlike the dbms_system and dbms_support packages, the dbms_monitor is a documented and supported package. You can also refer the documentation here Documentation for 10g

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The SQL_TRACE facility can be used at an instance level or at a session level. The trace file is generated by default in the directory
mentioned in the USER_DUMP_DEST parameter of the initialization parameter file.

You can also set an identifier for the trace file that is generated for easy identification.

Let us enable a trace for current session and see how oracle creates the trace file
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1. What is Tracing

In many situations, the DBA needs to collect detailed information on a SQL, session or a module to analyze a problem. This information can be used to optimise database performance or to suggest improvements to software developers, or sometimes just to understand what is going on.

Tracing is the process of collecting such information. Oracle also allows tracing of utilities like listener etc, but this article is restricted to session and sql tracing Read the rest of this entry »

1. What is a VPC ?

A virtual private catalog in Oracle 11g is a subset of the RMAN repository metadata. The repository owner can segregate and restrict access to the repository to other database users.

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