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 SQL tutorials by John Paul Ashenfelter written for

This is a wonderful collection of MySQL tutorials from which helped me tremendously to master the art. The only thing is that I didn't like the way their table of contents was done so I did my own, in chronological order, at least the ones by John Paul Ashenfelter. I have not had time to study the others yet. > MySQL Articles

MySQL Articles

What's the Big Deal about SQL? by John Paul Ashenfelter
SQL, the Structured English Query Language, is a standard for building relational databases. In this short introduction, author John Paul Ashenfelter explains relational databases and offers a history of the development and implementation of SQL.  Oct. 20, 2000

Getting Started with SQL by John Paul Ashenfelter
In the second half of his inaugural column, John Paul Ashenfelter introduces us to several good SQL learning tools and begins to define database terms.  Oct. 20, 2000

Introducing SELECT by John Paul Ashenfelter
The SELECT command helps you find the data in your database. Here's a hands-on tutorial on how it works. Oct. 27, 2000

Filtering SELECTed Data with WHERE by John Paul Ashenfelter
SQL databases can be filtered by virtually any set of criteria using a single clause. This week, John Paul Ashenfelter shows us how to use the SELECT command to return subsets of data. Nov. 3, 2000

INSERTing Data by John Paul Ashenfelter
We've spent a fair amount of time discussing how to get data out of MySQL. But can you enter data directly into this database? You can using the INSERT command. Nov. 10, 2000

UPDATE that Data! by John Paul Ashenfelter
Now that you have your data in MySQL, how do you change it? We'll show you step by step. Dec. 22, 2000

DELETE Tips and Tricks by John Paul Ashenfelter
This week John Paul Ashenfelter discusses the most dangerous of the core SQL statements: DELETE. Proceed with caution. Dec. 29, 2000

Where to Use WHERE by John Paul Ashenfelter
We're continuing our exploration of the WHERE clause by digging a little deeper into its capabilities to see what it can really do. Jan. 5, 2001

Using Functions by John Paul Ashenfelter
John Paul Ashenfelter continues his SQL tutorial with one of the most useful but most frustrating areas of SQL: built-in functions.  Jan. 12, 2001

Aggregate Functions by John Paul Ashenfelter
John Paul Ashenfelter looks at a specific class of SQL functions that operate on entire columns of data instead of discrete values -- the aggregate functions.  Jan. 30, 2001

Controlling Data Display with ORDER BY by John Paul Ashenfelter
This week, John Paul Ashenfelter revisits the ORDER BY clause to help you control the display of your MySQL data.  Feb. 13, 2001

Group By by John Paul Ashenfelter
The GROUP BY clause is the next step after mastering ORDER BY. John Paul Ashenfelter shows you how to combine database records into a single record to calculate an aggregate function.  Feb. 23, 2001

The "Key" to Good SQL by John Paul Ashenfelter
Database "keys" help eliminate confusion among records. Here's how to best incorporate these essential identifiers in your database. Mar. 6, 2001

Good Relations by John Paul Ashenfelter
John Paul Ashenfelter looks at how keys are used to construct relationships between tables in a relational database.  Mar. 13, 2001

Types of Relationships by John Paul Ashenfelter
How well are your database tables communicating with one another? This week John Paul discusses three key relationships: one to one, one to many, and many to many. Mar. 20, 2001

JOINed at the Hip by John Paul Ashenfelter
The JOIN clause is probably one of the most used -- as well as one of the most confusing -- facets of SQL. John Paul Ashenfelter introduces the JOIN clause.  May. 24, 2001

More on JOINS by John Paul Ashenfelter
The exploration into JOIN statements continues with a look at INNER JOIN, the most commonly used SQL join.  Jun. 1, 2001

Types of JOINs by John Paul Ashenfelter
A look at what's going on behind the scenes when you perform a "join" in MySQL. John Paul Ashenfelter uses the cross join as an example of how joins work in general. Jun. 15, 2001

The Outer Limits of SQL JOINs by John Paul Ashenfelter
In the last column, John Paul Ashenfelter showed you how to use inner joins and cross joins. This week he tackles outer joins. Jun. 27, 2001

Self-Inflicted SQL by John Paul Ashenfelter
This week, John Paul Ashenfelter looks at the "self-join," a tool that is particularly useful in certain situations, such as when you have a normalized database table that needs to be flattened. Jul. 12, 2001

SQL Subqueries by John Paul Ashenfelter
Subqueries are extremely useful in web-based database applications where you need to combine two queries and manually put them together to achieve a desired result. Subqueries allow SQL to do all of the heavy lifting! Jul. 26, 2001

Introducing SQL Sets by John Paul Ashenfelter
Because SQL is based on relational algebra, it should come as no surprise that the standard contains several set-oriented operators. In that spirit, it's time we take a look at the UNION operator. Aug. 2, 2001

Data Definition Language by John Paul Ashenfelter
GUI-based database management tools are great, but it's also important to understand the broad strokes of directly manipulating database structure. In this week's aboutSQL, John Paul Ashenfelter describes how to use SQL to define the database, its component tables, and other artifacts.  Aug. 30, 2001

Working With Tables by John Paul Ashenfelter
In the last aboutSQL column, John Paul Ashenfelter introduced the Data Definition Language (DDL) and how to create database containers. This week, he moves on to creating tables and populating them with data. Sep. 6, 2001

SQL Data Types by John Paul Ashenfelter
Most database products support ANSI-SQL for manipulating data, but there is far more variance in the details of how DDL is implemented. John Paul Ashenfelter discusses data types for different SQL platforms. Sep. 13, 2001

More MySQL stuff from

MySQL FULLTEXT Searching by Joe Stump
Storing text in your database is handy, but searching can be a pain. MySQL's FULLTEXT search can save your sanity. Joe Stump demonstrates how it works and gives several ideas on how to use it in your own applications. Jun. 26, 2003

Cooking with MySQL by Paul DuBois
Paul DuBois has selected sample recipes from the hundreds you'll find in his book, MySQL Cookbook. In this third and final series of excerpts showcasing these recipes, learn how to compute team standings, how to calculate the differences between successive rows, and how to find cumulative sums and running averages.  Dec. 26, 2002

MySQL Vulnerabilities by Noel Davis
Noel Davis looks at a problem with Perl's safe mode; some serious vulnerabilities in MySQL; buffer overflows in wget, tcpdump, Canna, and GTetrinet; and problems in lynx, mICQ, Sun Cobalt RaQ 4 Server Appliances, xdvi, dvips, and Exim. Dec. 16, 2002

Cooking with MySQL by Paul DuBois
Paul DuBois has selected sample recipes from the hundreds you'll find in his book, MySQL Cookbook. In this second article in a three-part series showcasing these recipes, find out how to manage simultaneous AUTO_INCREMENT values, and how to use AUTO_INCREMENT values and related tables. Dec. 12, 2002

MySQL Recipes, CVS Tools, and Disk Images by chromatic
Online version of the Linux Newsletter for November 25, 2002. Nov. 25, 2002

Cooking with MySQL by Paul DuBois
Paul DuBois has selected sample recipes from the hundreds you'll find in his book, MySQL Cookbook. In this first in a three-part series showcasing these sample recipes, find out how to interpret results from summaries and NULL values and how to identify duplicates in a table or record.  Nov. 21, 2002

Ten MySQL Best Practices by George Reese
George Reese, coauthor of Managing & Using MySQL, 2nd Edition, offers a set of best practices for MySQL administrators that will help with the security, maintenance, and performance of a MySQL installation. Jul. 11, 2002

Tips for Building Web Database Applications with PHP and MySQL by Hugh E. Williams
Here are eight tips for enhancing Web database applications by using PHP and MySQL. Apr. 4, 2002

An Introduction to PEAR by Joao Prado Maia
Find yourself wishing PHP had an easy way to manage additional modules? Joao Prado Maia explains PEAR and shows how it fills this role.  May. 25, 2001

MySQL File Overwrite Vulnerability by Noel Davis
Noel Davis shows us a buffer overflow in ASPSeek; a denial of service attack against timed; a new version of OpenSSH with many improvements; an attack against the private keys used by GnuPG; a race condition in the UFS and EXT2FS file systems; and problems with MySQL, VIM, FCheck, Solaris perfmon, Interchange, and Compaq's management software.  Mar. 27, 2001

MySQL Buffer Overflow; Secure PHP Coding by Noel Davis
Noel Davis shows us buffer overflows in MySQL, analog, vixie cron, and Kerberos IV; problems with kicq, licq, and kaim; root exploits in NetBSD i386 kernels; and insecure coding with PHP and MySQL.  Feb. 20, 2001

LAMP: The Open Source Web Platform by Dale Dougherty
O'Reilly Network runs a LAMP web site, and the chances are good that your organization does, too. LAMP = Linux + Apache + MySQL + (PHP | Perl | Python), and is our new site dedicated to the platform. Jan. 26, 2001

The Universal Web Form Processor by Urb LeJeune
Urb LeJeune embarks on a quest to create the ultimate script to process forms from web pages. Dec. 29, 2000

LAMP Lighter: The Apache Toolbox by Rael Dornfest
An overview of the Apache Toolbox, a Swiss army knife of a script, providing a customizable, menu-driven interface to downloading and compiling a LAMP (Linux, Apache, MySQL, PHPherlthon) -- minus the Linux -- installation. Nov. 17, 2000

OpenBSD as a Database Server by David Jorm
David Jorm explains the basics of setting up OpenBSD as a database server using MySQL/PostgreSQL and PHP. Oct. 17, 2000

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