This step should be simple. Run the Visual Studio 2008 SetUp program and check the “X64 Compilers and Tools” option under Visual C++
Apr 132010
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 code. As well as debugging the logging is very useful for automatically documenting formulae in JavaScript with worked examples that can then be pasted straight into the documentation.
An example of the logging capabilities can be seen on my sample OpenLayers page. If you already have Firebug installed you should be able to see the output similar to that below when the page loads.
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Mar 242010
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 be stored and accessed in a relational database using SpatialWare. Again to use ESRI terminology this is the ArcSDE equivalent. Fortunately MapInfo was quick off the mark in removing this barrier.
Access to SQL Server 2008 spatial data is provided by integrating FME functionality directly into the product, and having a “Universal Data” option on the File menu. There is also a tool named Easy Loader that allows loading .tab files into SQL Server as geometry.
Mar 112010
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 making.
The installation went well on the production server which was also a 64 bit machine, but was using Windows Server 2008. The site had an unpublicised release as it is still in beta, and from this was getting about 60 – 70 visitors a day.
I use host-tracker.com – a web site monitoring service which lets me know if a site is down, and I was soon made aware that it was.. There were no responses at all coming from Apache, even though the Apache service was still running. Not even HTML pages were returned. Restarting Apache returned the service to normal, but this was happening every other day.
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Jan 072010
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 15:28:21 2010].629000 msyyparse(): Expression parser error. syntax error [Thu Jan 07 15:28:21 2010].629000 msEvalExpression: Expression parser error. Failed to parse expression: ( >= 2.251) AND ( <= 2.5)
Map Server Logging
To turn on logging in MapServer Continue reading »
Jan 192008
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 closing secondary applications. The solution in the end turned out to be that the .ldb file had come under source control. Removing it from this, and deleting the fle resolved the issue.
Aug 142007
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 – Visual Source Safe can often be a culprit in setting this property..
- The SQL query may contain fields that are reserve words (e.g. DATE, TOP etc.). These should all be renamed in the database (I normally add an underscore at the end).
- Go through a long and tedious process of which Windows user is running the SQL (ASPNET, IUSR_COMPUTERNAME etc.) and check thy have write permissions to the folder containing the database, and the database file itself. Remember Access needs to create those pesky .ldb lock files..