Expert Oracle

Oracle Cloud Infrastructure (OCI) – 2 – Console

Published January 21, 2019 By Brijesh Gogia

Let us look at the Oracle Cloud Console in this post. Go to https://cloud.oracle.com/en_US/tryit and sign up for the Free Oracle Cloud Promotion. Please note you will need to add your credit card number but it will not be charged. There is no charge unless you choose to “Upgrade to Paid” from “My Services” console page.

Once your trial account is created you will become a tenant in Oracle Cloud Infrastructure. Oracle will send you a Welcome email which will have userid/password detailed to login to your “tenancy”.

Oracle Cloud Infrastructure supports the latest desktop versions of Google Chrome, Microsoft Edge, Internet Explorer 11, Safari, Firefox, and Firefox ESR. Note that private browsing mode is not supported for Firefox, Internet Explorer, or Edge. Mobile browsers are not supported.

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Oracle Cloud Infrastructure (OCI) – 1 – Fundamentals

Published January 21, 2019 By Brijesh Gogia

Cloud infrastructure is the most basic products delivered by cloud computing companies through the infrastructure as a service (IaaS) model. You can create your own IT infrastructure complete with processing, storage and networking resources. Cloud Infrastructure companies provide you flexibility in infrastructure design so these infrastructure setups can be easily set up, replaced or deleted as opposed to a physical one, which requires manual work.

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Performance Tuning Basics 16 : Using SQL Tuning Health-Check Script (SQLHC)

Published April 1, 2018 By Brijesh Gogia

This post will cover the SQL Tuning Health Check script basics and how you can use it to collect the key information regarding a poorly performing SQL. SQLHC helps you on focusing on specific SQL and checking Cost-based Optimizer (CBO) statistics, schema object metadata, configuration parameters and other elements that may influence the performance.

Unlike SQLT, this tool SQLHC do not require any code to be installed in the database to provide recommendation. SQLHC uses the SQL_ID of a statement that has already been executed and is in memory to generate the report so it do not actually execute the SQL all lover again. SQLHC works 10g and above. SQLHC is also RAC aware

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Physical and Logical Block Corruption in Oracle Database

Published March 10, 2018 By Brijesh Gogia

Block corruptions are one of the common source of database outages. A database block is corrupted when its content has changed from what Oracle Database expects. Correcting block corruptions can prove to be a lengthy and costly exercise and requires good expertise 0n the DBA part.

Block Corruption can happen at Logical level or Physical level. Also, such corruption can impact a single block or huge number of blocks in the database.

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Performance Tuning Basics 15 : AWR Report Analysis

Published February 6, 2018 By Brijesh Gogia

The Oracle’s Automatic Workload Repository (AWR) collects, processes, and maintains performance statistics for problem detection and self-tuning purposes. The report generated by AWR is a big report and it can take years of experience to actually understand all aspects of this report. In this post we will try to explain some important sections of AWR, significance of those sections and also some important tips. Please note that explaining all sections of AWR will not be possible so we will stick to some of the most frequently used sections.

Note that this is not comprehensive information and goal is to help in giving an overview of few key sections to Junior DBAs as a primer and to encourage them to build further the knowledge in related fields.

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Oracle Enterprise Manager (OEM) 13c – Part 3 : New Features in OEM 13c (13.2)

Published February 6, 2018 By Brijesh Gogia

OEM 13c (13.2) has many new features which make this version more useful than the previous OEM versions. If you are moving from OEM 12c to OEM 13c first change you will find will be that the appearance and look and feel of application is change a lot. In the starting you may feel little overwhelmed as you may be working for long in OEM 13c and may have got accustomed to it.

Some of the noteworthy new features of OEM 13.2 are mentioned below:

1. ENHANCED SUPPORT FOR VIRTUALIZATION SOFTWARES

Oracle VM enables virtual machines to be deployed, managed, and moved throughout Oracle’s public and private cloud infrastructure. Oracle Enterprise Manager 13c can manage Oracle VM technologies efficiently. The Enterprise Manager for Oracle Virtualization (VT) Plug-in has been extended to work seamlessly with Oracle’s latest server virtualization product, Oracle VM Release 3.4

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Oracle Enterprise Manager (OEM) 13c – Part 2 : Capabilities of OEM

Published February 6, 2018 By Brijesh Gogia

OEM tool has improved a lot in last decade. Oracle has added so many new features to it and fixed many software bugs. In coming years OEM will prove more important as the OEM capabilities are constantly increasing and the increasing trend of Hybrid setups (cloud and non-cloud) requires some monitoring tool which successfully monitors all kind of setups.

This post will describes some noteworthy capabilities of OEM and what all you can achieve by using OEM with your technological setups.

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Oracle Enterprise Manager (OEM) 13c – Part 1 : Basics and Architecture

Published February 5, 2018 By Brijesh Gogia

Oracle Enterprise Manager is Oracle’s solution to manage/monitor various database/applications which may be running on Cloud infrastructure or on-premise. OEM 13c is the latest version at the time of writing this post. In this post we will discuss about the architectural components which are required by Oracle Enterprise Manager.

Below is simple architectural representations of an OEM 13c setup.

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Performance Tuning Basics 14 : Active Sessions History (ASH) Basics

Published January 23, 2018 By Brijesh Gogia

The active session history (ASH) sampler performs the sampling. ASH samples the current state of all active sessions. The database collects this data into memory, where you can access it with a V$ view.

Using ASH enables you to examine and perform detailed analysis on both current data in the V$ACTIVE_SESSION_HISTORY view and historical data in the DBA_HIST_ACTIVE_SESS_HISTORY view, often avoiding the need to replay the workload to gather additional performance tracing information.

ASH also contains execution plan information for each captured SQL statement. You can use this information to identify which part of SQL execution contributed most to the SQL elapsed time. The data present in ASH can be rolled up on various dimensions that it captures, including the following:

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Performance Tuning Basics 13 : Automatic Workload Repository (AWR) Basics

Published January 23, 2018 By Brijesh Gogia

The Automatic Workload Repository (AWR) automatically persists the cumulative and delta values for most of the statistics at all levels except the session level.

This process is repeated on a regular time period and the result is called an AWR snapshot. The delta values captured by the snapshot represent the changes for each statistic over the time period.

The Automatic Workload Repository (AWR) collects, processes, and maintains performance statistics for problem detection and self-tuning purposes. This data is both in memory and stored in the database.

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Author: Brijesh Gogia