All SQL-compliant systems, including Microsoft JET SQL, have a set of functions to return computed results of numeric data stored in a column. All the aggregate functions create effects that

All of the aggregate components in Swing–that is, components made up other components, such as JTable, JTree, or JComboBox–can be highly customized. For example, a JTable component normally displays a

Environment variables are useful for gathering data about a client’s system settings, but different servers have different environment variables available to them. To find out what environment variables are available

Question: I developed a Web site with a database on my machine using Internet Information Server (IIS), Active Server Pages (ASP), and SQL Server. I want to install the site,

Question: What HTML tag do I use to have the screen refresh every two minutes? Answer: The following META tag will work. The value of the CONTENT parameter will determine

Question: I am designing a Web site for a conference. Over 2000 attendees are going to use the Web site for registering online, as well as for other interactive tasks,

Question: I am building Web pages using Visual Basic 6, Web Classes, HTML, DHTML, and JavaScript. Do you know of any good books that actually explain this type of programming?

Question: We have one phone line coming into the house. How can I get the phone to ring and the Internet connection to be broken if I’m on the net

Question: Can I use two submit buttons in the same form, but refer to two different scripts? Answer: Yes, it is possible to add two submit buttons to an HTML

In general, API functions and classes enable you to interact with the operating system. Sometimes, however, it is much simpler to execute a system command directly. For this purpose, you

When developing a database program, always keep the data-input user in mind. The most elegant program in the world is useless if the data is riddled with errors. If a

You can initialize a vector with the contents of a built-in array like this: #include#include using namespace std;int main(){ int arr[3]; arr[0] = 4; arr[1] = 8; arr[2] = 16;

Here’s a useful utility for finding the full pathname for a class (or any other file) from a Java program. This utility uses the method getClassNameFromPackage() described in the Tip

Although your Internet Service Provider (ISP) tells you the virtual directory that holds your Active Server Pages site, you may need to know the actual path where your files reside.

A reference is always bound to an object. In fact, you can think of a reference variable as an alias of its bound object. However, void& is not bound to

You can use a basic class finder utility to find the actual class file from a class. You can use the complete utility to locate a class file (or any

It’s fairly simple to customize the welcome message on your IIS/Windows NT FTP server. Welcome messages can contain directory information, usage guidelines, unauthorized access warnings, server news, and other useful

Use the #INCLUDE statement in your Active Server Pages (ASP) to utilize common code throughout your Web site. An Include file can contain client-side script, HTML or ASP. By coding

Question: I am using Visual Basic 6 and have a data grid referencing the Data environment command with a parameter. The grid won’t refresh to allow for different parameters. The

Cascading Style Sheets allow developers to exercise greater control over background images on the Web. You can make an image tile vertically across the page, horizontally across the page, or

To show when an icon button is disabled, you need to have a less prominent version of the icon’s image. The following class reduces the alpha component of each color

Question: I want to put a JTabbedPane on a tab of another JTabbedPane for using it as a chapter with different sections below it. How can I do this? Answer:

Question: Is it possible to load icons and other graphics into an application using a resource bundle? Answer: Resource bundles are intended to provide locale-specific resources so an application can

A predicate is an expression that returns either true or false. Similarly, a function object that returns a Boolean value is a predicate object. The Standard Template Library has several

When multiple inheritance is used, the memory layout of such an object is implementation-dependent. The compiler can rearrange the order of the inherited subobjects to improve memory alignment. In addition,

Question: I’ve written a page that uses expandable outlines using the display property of SPAN objects and it works fine in Internet Explorer 4. However, Netscape does not seem to

Question: I get a string from the Microsoft Index Server like this: “Information uber”. If I try to assign this string to a variable I get a runtime error: “Invalid

The last digit in your credit card number is a check digit derived from the other digits using the Luhn Formula as described in ISO/IEC 7812-1:1993. Its primary purpose is

VB supports conditional compilation, just like Visual C++. However, Visual C++ has a predefined constant named _DEBUG that makes it easy to include code only while debugging, as in this

Visual InterDev 6 colors HTML and script to make it easier to pick out the type of code and syntax errors. However, many programmers put frequently used routines in an