log4net AdoNetAppender not finding library file for ODBC - log4net

Question

I am trying to use log4net's AdoNetAppender to write a record to an event history table. We use ODBC because we have customers with various database systems, and ODBC is sufficient for our needs. However, I am not able to connect to my database. Here's my configuration file:
<?xml version="1.0" encoding="utf-8"?>
<log4net>
<appender name="ConsoleAppender" type="log4net.Appender.ConsoleAppender">
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date - %message%newline" />
</layout>
</appender>
<appender name="OdbcLogger" type="log4net.Appender.AdoNetAppender">
<connectionType value="System.Data.Odbc.Connection, System.Data"/>
<connectionString value="Dsn=Algoma;Server=localhost;Port=5432;uid=anneal;pwd=anneal" />
<bufferSize value="1" />
<commandText value="INSERT INTO event_history (description) values (?)" />
<parameter>
<parameterName value="message" />
<dbType value="String" />
<size value="4000" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%message" />
</layout>
</parameter>
</appender>
<root>
<level value="DEBUG" />
<appender-ref ref="ConsoleAppender" />
<appender-ref ref="OdbcLogger" />
</root>
</log4net>
I have log4net internal debugging turned on. Here's the exception message I'm getting:
log4net:ERROR [AdoNetAppender] ErrorCode: GenericFailure. Failed to load connection type [System.Data.Odbc.Connection, System.Data]
System.IO.FileNotFoundException: Could not load file or assembly 'System.Data' or one of its dependencies. The system cannot find the file specified.
File name: 'System.Data'
at System.RuntimeTypeHandle.GetTypeByName(String name, Boolean throwOnError, Boolean ignoreCase, Boolean reflectionOnly, StackCrawlMarkHandle stackMark, IntPtr pPrivHostBinder, Boolean loadTypeFromPartialName, ObjectHandleOnStack type)
at System.RuntimeTypeHandle.GetTypeByName(String name, Boolean throwOnError, Boolean ignoreCase, Boolean reflectionOnly, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean loadTypeFromPartialName)
at System.RuntimeType.GetType(String typeName, Boolean throwOnError, Boolean ignoreCase, Boolean reflectionOnly, StackCrawlMark& stackMark)
at System.Type.GetType(String typeName, Boolean throwOnError, Boolean ignoreCase)
at log4net.Util.SystemInfo.GetTypeFromString(Assembly relativeAssembly, String typeName, Boolean throwOnError, Boolean ignoreCase)
at log4net.Util.SystemInfo.GetTypeFromString(String typeName, Boolean throwOnError, Boolean ignoreCase)
at log4net.Appender.AdoNetAppender.ResolveConnectionType()
Can someone suggest what I'm doing wrong? Or perhaps show me an example of using an AdoNetAppender to write to a database via ODBC?
Thanks very much

Answer 1

I got it to work by specifying version number, public key and culture:
<appender name="OdbcLogger" type="log4net.Appender.AdoNetAppender">
<connectionType value="System.Data.Odbc.OdbcConnection, System.Data, Version=4.0.30319.18020,publicKeyToken=b77a5c561934e089,culture=neutral"/>
<connectionString value="Dsn=Algoma;Server=localhost;Port=5432;uid=anneal;pwd=anneal" />
<bufferSize value="1" />
<commandText value="INSERT INTO event_history (description) values (?)" />
<parameter>
<parameterName value="message" />
<dbType value="String" />
<size value="4000" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%message" />
</layout>
</parameter>
</appender>
I was wondering how to find the public key other than by luck in a Google search, which is how I found it. I found that gacutil will tell me.