Programming the Perl DBI
Author: Alligator Descartes and Tim Bunce
Publisher: O'Reilly & Associates
Price: $34.95 US
Reviewer: Bill Cunningham
This new book from O'Reilly is the first one available from any publisher on the subject of programming the Perl DBI, and its authors are imminently qualified to write it. Tim Bunce wrote the DBI Perl module, and also the DBD Oracle module. Alligator Descartes, who originally began working on the book, is a leading Perl/DBI exponent in the Oracle community. The authors have been working on the Perl interface to relational databases, and documentation thereof, since 1992. Programming the Perl DBI is not merely a republication of older documentation. A great deal of new material is here, not all of it about DBI.
The book starts out very simply, describing how even a flat file like /etc/passwd can be a bona fide database. The authors progress logically to more complex data models by addressing the shortcomings of the simpler models. After flat files, the book covers DBM and the Berkeley Database Manager, again noting the details of use, pros, cons and applications where this type of database is best used. A chapter on SQL and relational databases is included as a primer for those who are new to the material.
Three chapters deal with the theory and practice of using DBI to interact with various relational database engines. One chapter is devoted to ODBC. Every DBI method is described in detail and illustrated with at least one code example. There is also a chapter on DBISH, the DBI shell, wherein one can interactively give commands to the database after the manner of Oracle's SQLPlus. This tool will be valuable during development of database programs.
The book includes a description of a complex relational model where Microsoft clients access UNIX servers and vice versa over a network, with data encrypted via software.
The appendices contain a complete DBI specification, and specific information for each of the major relational engines.
The authors assume the readers have significant fluency with Perl, including installation and use of Perl modules and Perl's object-oriented syntax. Although the code examples are short, numerous and well-documented, readers new to Perl may need a Perl reference as they go through the code.
As a one-source database reference, the book is essentially complete. Detailed treatment is given to the DBI/DBD concept where each database engine has a unique driver (DBD), and a DBI superlayer that provides transparency to the engine below. All of the DBI methods are covered in detail, so the reader is able to select methods appropriate to his or her programming tasks. The authors are especially thorough in their treatment of debugging levels, error trapping and error interpretation.
They state that DBI is very much a work in progress and envision it to be a full-featured product soon, on par with any commercial development product available.
I noticed only two minor typos in the entire book. This was quite refreshing to me, as I have read computer books containing so many errors as to be virtually useless.
Anyone who works with data will find this book useful. And the more closely one works with relational databases and the programs which access that data, the more useful it will be.
Practical Task Scheduling Deployment
July 20, 2016 12:00 pm CDT
One of the best things about the UNIX environment (aside from being stable and efficient) is the vast array of software tools available to help you do your job. Traditionally, a UNIX tool does only one thing, but does that one thing very well. For example, grep is very easy to use and can search vast amounts of data quickly. The find tool can find a particular file or files based on all kinds of criteria. It's pretty easy to string these tools together to build even more powerful tools, such as a tool that finds all of the .log files in the /home directory and searches each one for a particular entry. This erector-set mentality allows UNIX system administrators to seem to always have the right tool for the job.
Cron traditionally has been considered another such a tool for job scheduling, but is it enough? This webinar considers that very question. The first part builds on a previous Geek Guide, Beyond Cron, and briefly describes how to know when it might be time to consider upgrading your job scheduling infrastructure. The second part presents an actual planning and implementation framework.
Join Linux Journal's Mike Diehl and Pat Cameron of Help Systems.
Free to Linux Journal readers.Register Now!
- SUSE LLC's SUSE Manager
- My +1 Sword of Productivity
- Managing Linux Using Puppet
- Non-Linux FOSS: Caffeine!
- Murat Yener and Onur Dundar's Expert Android Studio (Wrox)
- SuperTuxKart 0.9.2 Released
- Doing for User Space What We Did for Kernel Space
- Google's SwiftShader Released
- Parsing an RSS News Feed with a Bash Script
- SourceClear Open
With all the industry talk about the benefits of Linux on Power and all the performance advantages offered by its open architecture, you may be considering a move in that direction. If you are thinking about analytics, big data and cloud computing, you would be right to evaluate Power. The idea of using commodity x86 hardware and replacing it every three years is an outdated cost model. It doesn’t consider the total cost of ownership, and it doesn’t consider the advantage of real processing power, high-availability and multithreading like a demon.
This ebook takes a look at some of the practical applications of the Linux on Power platform and ways you might bring all the performance power of this open architecture to bear for your organization. There are no smoke and mirrors here—just hard, cold, empirical evidence provided by independent sources. I also consider some innovative ways Linux on Power will be used in the future.Get the Guide