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Format Function In SQL Statement

Question: I want to assign the result of a SQL statement to a multi-line text box, and I want to format the individual fields using the Format function. Can I

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Database Connection from ASP to dbase IV

Question: I have made a databaseconnection to a dbase IV database in VisualInterdev (with global.asa). In the Data View window I can see the tables, but when I open a

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Cross-midnight time measurements

Any time the behavior of your code depends on the Timer function you should take into account the (more or less) remote possibility that your code is executed just before

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Check a GUID

The following routine quickly check that a string contains a valid GUID. Of course, it doesn’t check that the GUID refers to a valid entity, but at least it lets

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A VarPtr substitute function for VB4

Both VB5 and VB6 include a hidden function, named VarPtr, that returns the address of a variable. Many advanced tricks and routines, on VB2TheMax or other site, use this function.

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How to View the Source of External JS Files

You can use an external JS file to store modular JavaScript code. In addition to being modular, it hides your JavaScript code from novice users. However, it is possible for

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Get a Hold of Swing Defaults

Swing is one of the best things that happened to Java GUI developers. At the heart of Swing is the javax.swing.UIManager class (com.sun.java.swing.UIManager for Swing 1.03 and below) that keeps

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Use Stored Procedures in Place of Embedded SQL

Stored procedures offer many advantages over dynamic SQL, including improved performance and scalability. The SQL code in a stored procedure is parsed and normalized when you create it. Stored procedures

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Do Not Use Operator New in a Throw Statement

Dynamic allocation of an exception (as in this example) is not a good idea: class Err{public: Err(const char * description);};void f(){ if (disaster) throw new Err(“failed”); //exception object is dynamically

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One More Reason to Avoid Macros

Even macros that look harmless can have detrimental effects. For example: #define twice(x) ((x)+(x)) The macro, twice, is well parenthesized and performs a simple addition operation. Despite its simplicity, there

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The Organization of STL Header Files: Container Classes

STL is divided into two major categories: containers and algorithms. Additional components are iterators, function objects, numeric facilities, allocators, and miscellaneous utilities. STL containers are defined in eight different header

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Guidelines for Writing Portable Code

As opposed to what most people believe, portability does not guarantee that you can compile and run the same code on every platform without any modifications. Although it is sometimes

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Load a Grid from a SQL Statement

Use this code for a generic routine to load a grid from a SQL statement. The example is for Remote Data Objects (RDO) and Sheridan Software Systems’ grid, but it

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Invisible Control Placement on MDIForm Client Area

With VB4 or higher, you can place invisible controls-such as the standard Timer and CommonDialog or UserControls built with VB5 that have their InvisibleAtRuntime property set-directly on an MDIForm. In

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A Better Use for StrConv

When using proper names, you sometimes need to capitalize the first letter of each word. For example, you need to convert “john smith” into “John Smith.” With VB3, you had

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Max users

Question: I have 20 user licenses. During some activities, users are being logged in two or three times. Thus I can hit a max user limit with only 9 actual

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SQL Tutorials

Question: I am interested in learning SQL on my own and need to know if there are any tutorials or disks that I can obtain so that I can practice

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SQL: querying records based on ORDER BY

Question: Can you make a query that returns records based on ORDER BY something? There may be mutiple instances, but I only want the one that is the very first

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Establish Referential Integrity

Question: How do you Establish Referential Integrity between 2 tables so that when a ticket is deleted from the TICKETS table all associated information in the customer5 table will be

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How to find the top percentage of users

Question: I want to find out the top 5%, 10%, and 30% customers based on their purchases. For example, my table looks like:CustomerID Purchase(in $)1 1002 500Up to 100 customers.

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Designing a keyord search query in Access

Question: I’m still quite new to using SQL and I am designing a database in which I am cataloging resources owned by my company. I am attempting to create a

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Error messages

Question: In SQL Server 6.5, what is the meaning of ‘Error States’? I get this message in a stored procedure.What are these states 1-27. Answer: These numbers provide the context,

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SQL Substring searches

Question: How do you select all entries that contain a certain substring? Is there a function like InStr() in VB? Answer: Yes, Check out the charindex function which will Return

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Coding blank spaces in a select statement

Question: After the line break in the code below, the blankspace between the quotes is not recognized. I am merely trying to indent the second line, but I get nothing.

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Datatype – TEXT

Question: I have fields, in which the datatype is TEXT, and I need to know how I can insert and update data from these fields? Answer: If the size of

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SQL Server Performance

Question: I have developed an application that processes about 40,000 records every time it runs. I am using ADO 2.1 and each record is returning about 100 columns of data,

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Cascade Delete

Question: What is the syntax for doing a cascade delete in SQL? For instance, I have a table with a parent record that has child records in other tables, filtering

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SQL UPDATE 2 TABLES

Question: In all the Foxpro 5.0 documentation, I can’t find an example on how to update the contents of a field ofa table based on another table. For example, table