Setting up Visual Studio 2008 for Compiling 64-bit DLLs

This step should be simple. Run the Visual Studio 2008 SetUp program and check the “X64 Compilers and Tools” option under Visual C++

Logging OpenLayers with Firebug

I take it as given that anyone developing with Firefox and OpenLayers has Firebug installed. Firebug has a number of powerful tools that can make the previous nightmare of JavaScript debugging tolerable. One feature I recently “discovered” are the logging options. It’s definitely a timesaver over my previous method of putting temporary alert(vals); throughout my […]

MapInfo and SQL Server 2008

For a new project I am working for the first time with MapInfo 10 “the world’s premier desktop mapping application.” In an effort to move away from MapInfo’s .tab files (the shapefile equivalent) I was keen to test out the direct connection to geometry stored in SQL Server 2008. Until version 9.5 data could only […]

MapServer+Windows 64 bit+Apache=Crash?

I developed my MapServer application on Windows 2003 (a virtual 64 bit server running), using MS4W (MapServer for Windows), and had set up TileCache, and some Python scripts to run through Apache. I had managed to crash the set up numerous times in development, but I hadn’t come across any errors not of my own […]

Map Server Expression Errors

Errors… After turning on logging to diagnose an issue with MapServer I found a more worrying error, that was causing the log file to fill up at a rate of about 2MB a minute! I was reusing a legend for five or six datasets, and it was causing the following debug notes: [Thu Jan 07 […]

Could not use ''; file already in use."

System.Data.OleDb.OleDbException occurred   ErrorCode=-2147467259   Message=”Could not use ”; file already in use.”   Source=”Microsoft JET Database Engine” Access, lock files, and Visual Source Safe – an accident waiting to happen! I got the above error, after my code had been fine for weeks. Googling turned up permissions on the folder with the Access database, and […]

Operation must use an Updateable Query

I know I see this error about once a year and can never remember the cause, so I’m writing it down this time! In my case it has always been related to SQL queries and Access databases. Check the following if your SQL command produces this error when executed: The database is not read only […]