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Application Architecture
9/7/2007Table-Driven and Data Driven Programming

Discusses what table and data-driven programming is and how it is used.
11/30/2005Choice Between Stored Procedures, Functions, Views, Triggers, Inline SQL (updated)

There has been a lot of debates around when to use stored procedures vs. raw sql. Many purists are vehemently on one side of the fence or the other. Strangely people talk about views to a lesser extent. Stored functions and triggers are almost nonexistent in these debates. In this article we'll try to provide a non-biased outline of the benefits and pitfalls of each approach.
7/19/2003Separation of Business Logic from Presentation Logic in Web Applications (ASP.NET and PHP)

In this article we contrast and compare two approaches for separating business logic from presentation logic using two of our favorite web development languages: The template approach commonly used in PHP and the Code-behind approach found in ASP.NET.
10/15/2002Guidelines for a Successful Application

This article provides some general guidelines for building a good Application. These lessons are based on our personal experiences and observations. Note that many of these guidelines may contradict what "Experts" will tell you.
Microsoft Office VBA
8/11/2001Rendering the results of an Access Database in Excel

In this article we will demonstrate how to populate an excel spreadsheet with data from an Access database
5/26/1999Using Excel As a Reporting Engine

Excel can make a great reporting engine if one understands how to use its automation objects. In this article we demonstrate how to create excel spreadsheets, set cell values, formulas and more sophisticated things with Office Excel VBA.
5/22/1999Building a Data Dictionary in Access 97

A great deal of information can be stored in table definitions of Access databases. In this article, we demonstrate how the table definition information in an Access Database can be retrieved to build a data dictionary for an Access application.
Relational Databases
3/16/2008PostgreSQL - Recursive table returning functions

In a prior article we discussed how to use PostgreSQL user-defined functions to solve the recursive tree problem and return a concatenated string of the result. In this article we demonstrate how to return the value in a table instead of as a string.
12/26/2006What is a cross tab query and how do you create one using a relational database?

In this article we will define what a cross-tab query is and how to create one. We will provide examples for Microsoft SQL Server, Microsoft Access, PostGreSQL, and MySQL, Oracle
10/31/2006Brief Summary of Popular Database Systems

This upcoming year will prove to be an exciting one for database technology. Many database vendors are coming out with milestone versions of their DBMS systems.

This article covers the primary database systems we use and what each holds in store this year. While we can't cover all databases here, we'll cover the ones we are most familiar with. We will cover what their current state is and what their future direction is. We will focus our attention on MySQL, PostGreSQL, and SQL Server
6/3/2006SQL Cheat Sheet: Query By Example - Part 2

In this article, we'll cover some more SQL tricks for accomplishing tasks such as getting the details of the newest record from a relational database.
7/2/2005SQL Cheat Sheet: Query By Example

In this sql cheatsheet we will provide some common query questions asked and SQL solutions to these questions. Most of these examples are fairly standard ANSI-SQL so should work on most relational databases such as PostGreSQL, MySQL, Microsoft SQL Server, Oracle, Microsoft Access. Some examples involving subselects or complex joins may not work in most versions of MySQL and some versions of Microsoft Access
2/15/2004Using PostgreSQL User-Defined Functions to solve the Tree Problem

In a prior article we discussed how to use SQL Server's user-defined functions to solve the recursive tree problem. In the SQL version we solved the common who reports to who problem. In this article we demonstrate how to solve the classic tree problem using PostGreSQL user-defined functions. We will use a different example.
6/13/2003Databases: Past, Present, and Future

This article is dedicated in memory of Edgar F. Codd - Father of Modern Relational Database Theory. In this article we will delve into the history of databases - how it started, where the industry is now and what its potential achievements will be.
6/4/2002PostgreSQL: An Open-Source Object Relational Database Management System (ORDBMS)

In this article we will delve into the features of the PostgreSQL object-relational database environment and what makes it special. We will focus on features that make PostgreSQL different from most relational database management systems (RDBMS).
4/16/2001Using SQL Server 2000's User Defined Function to solve the Tree Problem

In this article we demonstrate how to solve the classic "Who does an employee" report to problem using SQL Server 2000's new User-defined function feature
9/8/2000Summarizing data with SQL (Structured Query Language)

This article provides a brief SQL How-to on how to summarize data. Most of the examples we provide will be based on the ANSI-SQL 92 standard. Some examples will show features specific to SQL Server 7.
Server-Side Scripting (Web Programming)
3/14/2003Calling Webservices from ASP.NET: Example Google Web Service

We describe what a web service is, how to call webservices in ASP.NET. We provide the Google Search web service as an example.
10/7/2002Tagging Along with ASP.NET, JSP and ColdFusion

In this article we focus on using server-side tags in web programming. We compare three offerings and how they approach server tags.
12/20/2001Web Programming with PHP - Why choose PHP?

In our article Active Server Pages (ASP), Java Server Pages (JSP), Cold Fusion (CFM) - A comparative analysis., We neglected to include PHP. PHP is a language that has been around for a few years and that appears to be gaining quite a bit of popularity.
4/26/2000Active Server Pages (ASP), Java Server Pages (JSP), Cold Fusion (CFM) - A comparative analysis

In this article we provide a comparison of 3 server side scripting technologies by detailing the main features of each. We end with a comparison chart that ranks each by ease of use, capability, and costs.
1/25/2000Database Web Programming with Cold Fusion

This article provides a brief synopsis of some key Cold Fusion Tags and functions that a web developer will need to produce active database content in Cold Fusion.
7/27/1999Building an Excel Spreadsheet using ASP

In this article, we demonstrate a simple approach to build an Excel 97/2000 spreadsheet in ASP.
10/1/1996Detecting Invalid Messages within a Method Definition

Smalltalk is an untyped language. As a result one can make syntactically correct statements that are meaningless. This flaw often gets caught only at run-time. This article describes how to trap such flaws before execution time.
10/1/1996Implementing State-based Testing in Smalltalk

This article describes the principles of state-based testing and how to implement such a system in the SmallTalk language.
Theory and Concept
10/1/1996Monitoring Business Objects with ECA

This article we presented at the 1996 OOPSLA conference outlines an approach to implementing business rules in an object oriented environment - using the concept of Events, Conditions , and Actions.
2/15/1996Business Rules and Object Orientation

This article details guidelines for setting up business objects and a sample implementation of a rules processor.
10/1/1995Use of Matrices in Identifying and Reorganizing Class Hierarchy

This article details a mathematical approach based on matrix algebra to determine flaws in OO class hierarchies and package dependencies.