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Enable or Disable Triggers on SQL Server 7.0

You can enable and disable triggers on tables for SQL Server 7.0. This means you don’t need to drop triggers and recreate them if some process (which requires that triggers

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Validate a Drop-Down List on a Form

The easiest way to make ensure that a user picks a value from a dropdown list is to add a value to the top of the list that isn’t really

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Accessing a C++ Object in C Code

C code, which of course is unaware of object semantics, can access the data members of a C++ object directly, but certain requirements must be met. There are some guarantees

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Threading Piped Streams

Piped streams are typically used in separate threads. One thread writes output to a PipedOutputStream. The other thread reads the same data from a PipedInputStream. The two streams are connected

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Running Piped Threads

In a typical application using piped streams, an object of type PipedInputStream and an object of type PipedOutputStream are started as separate threads. One thread uses a PipedOutputStream to output

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Set Objects to Nothing

If you set objects to Nothing, then test their nothingness, this suggestion might help you. If you declare an object as New and later set it to Nothing, VB won’t

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Hashed Associative Containers

The Standard Template Library (STL) provides only one type of associative container–the sorted associative container. The STL sorted associative containers are map, multimap, set, and multiset. However, there is another

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Track MousePointer Changes

If you develop large apps, this routine can help you keep a count of calls to change the mousepointer. The routine, called MouseStack, keeps a stack of those calls and

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Scrub Out Unused Constants

Low-level parsing in VB doesn’t come up every day. This routine demonstrates how to search a VB module for dead module-level constants with only a few lines of code. Reading

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Identities and Triggers—A Lethal Mix

he identity property is a useful tool in designing databases. However, you can encounter serious problems with using it when combined with triggers. This problem was brought to my attention

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Obtain the ASCII Value of a Character

To obtain the ASCII value of a character, simply assign the char variable to an int variable. For example: char aChar=’B’;int charVal = aChar; Then System.out.println(“”+charVal); will print the ASCII

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Simplify Command-Line Argument Parsing

ArgumentParser simplifies command-line argument processing by separating arguments into positional parameters and options (any argument starting with “-” or “/” is considered an option, which may specify a value). Construct

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Create C++ DLLs to be Used in VB Apps

Some C++ programmers develop Win32 API DLLs that can used from Visual Basic programs. Use the __stdcall prefix with functions exported from the C++ DLL that you want to access

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Move the Cursor to the Center

Use this simple subroutine to move the mouse/cursor to the center of an object. It’s useful for tab-like functions and default settings: Private Declare Function SetCursorPos& Lib _ “user32” (ByVal

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Assure Compatibility

When working with ActiveX DLLs, many VB programmers build a reference DLL first, copy it to a subdirectory of the project directory, and set version compatibility to binary with a

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Never Store Arrays of Objects in an auto_ptr

The Standard Library’s auto_ptr class template automatically destroys an object that is allocated on the free store when the current scope is exited. For example: #include //definition of auto_ptr#include using

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Add a Hyperlink Listener in Java

To add a hyperlink listener in Java, add it to the JEditorPane and set its contents. A lot of errors may be thrown, but this is how the hyperlink listener

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Dump the Server Variables to a Table With ASP Code

The Active Server Pages Request object gathers lots of information about the server and the browser. This information is stored in the ServerVariables collection. You can iterate through the entire

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The Default Value Returned From main()

In this example, main() is missing an explicit return statement. int main() { printf(“hello world”); } In C, when control reaches the end of main() without encountering a return statement,

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Create ODBC DSNs Dynamically

You can use Visual Basic to create ODBC Data Sources Names (DSNs) dynamically for MS SQL Server. Simply place this line in a module: Declare Function SQLConfigDataSource Lib “odbccp32.dll” (ByVal