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One obvious way to display or filter large recordsets is alphabetically. This function will take a page file and an optional frame name (defaults to _self) and create a row
You can call a function from a link, instead of opening a new location, by assigning the function to the anchor tag’s href attribute, like this: Click here Notice that
Question: When I use a datawindow to generate a custom report, how can I pass a variable into the report from an input field? Answer: You can do this through
Question: About halfway through compiling a 32-bit EXE with PB 6.5 on Windows NT, I keep getting an “out of memory” message box and then another that says “DDE Server
Question: Can I insert comments inside a SQL query, like /* */ and //in C++? Answer: SQL supports /* and */ for comments inside stored procedures and queries. You also
Question: I have several tables with the same structure and I’m trying to combine them all into one unique table. But I’m worried about performance because each table has a
Question: When I try to create a new IIS app,I receive an error message: “IIS or peer web services 3.0 or latermust be installed,” but IIS is installedand running on
Question: Can three versions of PB (5.0, 6.5, and 7.0) coexist on the same machine without any problems? Answer: I am running PB5.0.4, PB6.5, and PB7.0.1 on my home and
Question: How do I test the number of ‘characters’ contained within a given variable? Answer: Try this: Debug.Print “Length: ” & Len(CStr(X)) Once you convert a variable to a string,
Question: How do I use the ADO events FetchProgress or FetchComplete? Answer: If you want to use these, they work just like other events generated by other objects. When you
Question: What is the proper syntax to insert a column into an existing SQL table? Answer: Here’s the syntax to add a column to a table: ALTER TABLE Employees ADD
Question: Using a single datawindow, can I access data from multiple databases (Oracle and Sybase)? If not, can I use PowerBuilder to access it without having any intermediate table? Answer:
STL’s unique() algorithm eliminates all but the first element from every consecutive group of equal elements in a sequence of elements. unique() takes two forward iterators, the first of which
A bit field can be signed or unsigned. According to the C++ standard, a signed bit field may be represented in one of three ways: two’s complement one’s complement sign
Although usually I don’t recommend using macros in C++ code, there are a few exceptions. One such exception is when you want to create a truly immutable constant. Consider the
If you happen to define an object or a function or a constant whose name collides with a macro located elsewhere in a third-party header file, as in: // file
Open source products come with their source code files. Although you can usually install a ready-made executable file, you want to take advantage of the available source code files and
Many modern operating systems support Symmetric Multiprocessing (SMP)?a hardware architecture that uses two or more processors on one machine and enables you to achieve true multitasking. On SMP architectures, multithreaded
The members of an enumerated type are called enumerators. For example: enum Direction { Up, // an enumerator Down // another enumerator }; int main() {} An enumerator’s scope is
I receive many questions from readers asking for guidance on how to port an existing C++ app to a different compiler or platform. Porting software can be very easy or
On modern operating systems, a process consists of an executable file that the OS loads into the system’s memory and executes. A process normally has an entry point and one
Question: How do I drop a table column? Answer: To drop a column, use this syntax: ALTER TABLE Employees DROP COLUMN HomePhone Just remember that you can’t drop a column
Question: How do I create a constructor for a protected member of a class? I have declared the function in the header file but not defined the definition.The error message
Question: I need a query that retrieves info from an Oracle table and a query that retrieves info from a SQL Server table. The info has to be joined together
Question: What are the differences between Provider=MSDASQL.1 and Provider=SQLOLEDB.1 in an “Open” “Select” statement? Also, what is the difference (if any) between “ADO” AND “OLE/DB”? And finally, in Visual Basic,
Question: I have two questions: 1. How can I determine what the server’s lock mode currently is (e.g. WAIT, NO WAIT, etc.), without actually setting it at the same time?
Question: What’s the syntax for outer joins in the where clause in Informix? Answer: The syntax is: SELECT c.customer_num, c.lname, c.company,c.phone, u.call_dtime, u.call_descrFROM customer c, OUTER cust_calls uWHERE c.customer_num =
Question: Using C or C++ for CGI programs, is there a way to make a CGI program that calls another CGI program, and then takes the output of that called
Question: If I have the option of using the uniqueidentifier or int data type for a primary key, will choosing the uniqueidentifier mean a significant performance degradation? Answer: The uniqueidentifier
Const HKEY_LOCAL_MACHINE = &H80000002′ Return True if the system has a math processor” Requires the CheckRegistryKey routineFunction CheckMathProcessor() As Boolean ‘ if a math processor exists, Windows creates ‘ the











