February 2015

Database Provisioning in Minutes: Using Enterprise Manager 12c DBaaS Snap Clone and EMC Storage

A little while back I posted a blog on the official Oracle Enterprise Manager blog on using Enterprise Manager 12c Snap Clone with EMC storage. Last week, I also presented on exactly the same topic at the RMOUG Training Days in Denver, Colorado, and there was quite a bit of interest in the subject.

Understanding enhancements to block cleanouts in Exadata part 1

Travel time is writing time and I have the perfect setting for a techie post. Actually I got quite excited about the subject causing the article to get a bit longer than initially anticipated. In this part you can read about block cleanouts when using buffered I/O. The next part will show how this works using direct path reads and Smart Scans.

The article ultimately aims at describing the enhancements Exadata brings to the table for direct path reads and delayed block cleanouts. Delayed block cleanouts are described in Jonathan Lewis’s “Oracle Core”, and in one of his blog posts, so here’s just a summary.

The delayed block cleanout

Return of the Disasters – OUG Ireland 2015

In just under a month I’ll be off to Dublin for the 2015 OUG Ireland conference. It takes place on Thursday the 19th of March. I’m doing my favorite presentation to present, on I.T. disasters I have witnessed and what you can learn from them (so now the title of this blog makes sense and maybe is not as exciting as it suggested). It is also the talk I get most nervous about doing. I tend to put a bit of humour into any presentation I do but if it is predominantly a technical talk, it’s fine if the humour falls flat. When I am intending to be entertaining, as I do with this one, there is more at stake!

PeopleTools 8.54: Multiple Query Security Records

This is part of a series of articles about new features and differences in PeopleTools 8.54 that will be of interest to the Oracle DBA.

This post is not about a database feature newly supported in PeopleTools, but PeopleTools is capable of doing something new that could negatively impact the database.  When I saw the following warning in the PeopleTools 8.54 release notes, I thought I should look into it.

PeopleTools 8.54: Multiple Query Security Records

This is part of a series of articles about new features and differences in PeopleTools 8.54 that will be of interest to the Oracle DBA.

This post is not about a database feature newly supported in PeopleTools, but PeopleTools is capable of doing something new that could negatively impact the database.  When I saw the following warning in the PeopleTools 8.54 release notes, I thought I should look into it.

PeopleTools 8.54: Materialized Views

This is part of a series of articles about new features and differences in PeopleTools 8.54 that will be of interest to the Oracle DBA.

Materialized Views in the Database

Snapshots were introduced in Oracle 7.  They were a way of building and maintaining a physical table to hold the results of a SQL query.  We are well used to a view being the results of a query, but here the results are materialised into a physical table.  Hence the feature was renamed materialized views in Oracle 8i.

Today materialized views are one among many replication technologies.  They are available in standard edition Oracle, and there is no licensing implication in their use.

Materialized views can generally be put into two categories

PeopleTools 8.54: Global Temporary Tables

This is part of a series of articles about new features and differences in PeopleTools 8.54 that will be of interest to the Oracle DBA.

Database Feature Overview

Global Temporary tables were introduced in Oracle 8i.  They can be used where an application temporarily needs a working storage tables.  They are named

  • Global because the content is private
  • Temporary because the definition is permanent

Or if you prefer

PeopleTools 8.54: Table/Index Partitioning

This is part of a series of articles about new features and differences in PeopleTools 8.54 that will be of interest to the Oracle DBA.

Partitioning in Oracle

Partitioning of table (and index) segments involves breaking them into several smaller segments where certain data values only occur in certain segments.  Thus if a query is looking for a certain data value it may be able to eliminate some partitions without having to scan them because by definition those values cannot occur in those partitions.  Thus saving logical and physical read, and improving performance.  This is called partition elimination or pruning.  It is often the principal reason for partitioning a table.

PeopleTools 8.54: %SQLHint Meta-SQL

This is part of a series of articles about new features and differences in PeopleTools 8.54 that will be of interest to the Oracle DBA.
 
This new PeopleCode meta-SQL macro performs a search of SQL statement for the nth instance of SQL command keyword and inserts a string after it.

PeopleTools 8.54: %SelectDummyTable Meta-SQL

This is part of a series of articles about new features and differences in PeopleTools 8.54 that will be of interest to the Oracle DBA.
  
PeopleTools simply evaluates this meta-SQL as 'DUAL' on Oracle.

In Oracle, DUAL is just a convenience table.  You don't need to use it, you can use anything you want. PeopleSoft applications often use PS_INSTALLATION when they needs a single row source in a query.  This was another example of platform agnosticism.  PS_INSTALLATION is available on every platform and every PeopleSoft installation, DUAL is not.

Instead of coding this (the example is taken from ESPP_REF_REVMAIN.PSHUP.Do When)