Calvin Hsia's WebLog

In this post DECLARE DLL performance questions I asked whether using the WIN32API keyword or the particular DLL file name would be faster. It turns out that Win32API is much faster, and Martin Jindra, Timo, and Fabio Lunardon answered correctly that with...

I was writing a sample about DECLARE DLL to show some of its features which I implemented about 12 years ago, when I rediscovered an interesting performance issue. The purpose of DECLARE DLL is to allow the user to call functions in a DLL directly...

I was reviewing some code changes, and I noticed some of the lines were quite different in length. I wrote some code to figure out why. I thought initially that I would just create a cursor with a field of length 250 and then use the APPEND FROM...

I was writing some code to test Microsoft SQL Server: SQL Server 2005 Express Edition (which I believe you can download for free) It connects to SQL Express (It’s simple change to use SQL Server 2005), creates a database called Test, creates a table...

Run the code below. How many times is the function FOO called? Why? The first SELECT is a single table query. The next is a 2 table self-join with no join condition. PUBLIC nCount nCount= 0 CREATE CURSOR test ( name c( 10 )) nRecs...

I received a question from a reader: I decided to extend my VPF9SP1 application to support OLE Automation like MS Office. I'd like to enable user (through code, i.e. VBA macro in Excel) to instantiate my app, create a new form, fill-in some data...

I received a question regarding this post: How do large programs work? Hi Calvin. I thought we're supposed to write granular, encapsulated programs. I have read that the highest quality code is also some of the smallest code. If that's true, then...

Several months ago, I wrote The mechanics of Sudoku and Sudoku puzzles screen capture . As a result, Stephen Toub emailed me and asked if I’d like to beta test his Tablet PC version of Sudoku. He sent me several versions over the next few months to...