Log4Net exception while writing exception to MySQL database

Question

When logging an exception, it is correctly shown in the command line. However, it does not write to the database. The other parameters are logged correctly.

In my app.config, the exception is configured as follows:

<commandText value="INSERT INTO logs (time, log_level, logger, message, exception, thread) VALUES (?time, ?log_level, ?logger, ?message, ?exception, ?thread)" />

Parameter:

<parameter>
    <parameterName value="exception" />
    <dbType value="String" />
    <size value="2000" />
    <layout type="log4net.Layout.PatternLayout">
        <conversionPattern value="%exception" />
    </layout>
</parameter>

I am testing with:

try
{
    throw new DivideByZeroException();
}
catch (Exception e)
{
    log.Error("", e);
}

I enabled Log4Net debugging and got the following output:

log4net: Hierarchy Threshold []
A first chance exception of type 'System.FormatException' occurred in mscorlib.dll
log4net:ERROR [CustomAdoNetAppender] ErrorCode: GenericFailure. Exception while writing to database
12:25:37,902 [Game.Program] {exceptions} () ERROR:  System.DivideByZeroException: Attempted to divide by zero.
   at Game.Program.Init() in --:line 98

log4net:ERROR [CustomAdoNetAppender] ErrorCode: GenericFailure. Exception while writing to database
System.FormatException: Input string was not in a correct format.
   at System.Number.StringToNumber(String str, NumberStyles options, NumberBuffer& number, NumberFormatInfo info, Boolean parseDecimal)
   at System.Number.ParseInt32(String s, NumberStyles style, NumberFormatInfo info)
   at System.String.System.IConvertible.ToInt32(IFormatProvider provider)
   at System.Convert.ToInt32(Object value)
   at MySql.Data.Types.MySqlInt32.MySql.Data.Types.IMySqlValue.WriteValue(MySqlPacket packet, Boolean binary, Object val, Int32 length)
   at MySql.Data.MySqlClient.MySqlParameter.Serialize(MySqlPacket packet, Boolean binary, MySqlConnectionStringBuilder settings)
   at MySql.Data.MySqlClient.Statement.SerialiSystem.FormatException: Input string was not in a correct format.
   at System.Number.StringToNumber(String str, NumberStyles options, NumberBuffer& number, NumberFormatInfo info, Boolean parseDecimal)
   at System.Number.ParseInt32(String s, NumberStyles style, NumberFormatInfo info)
   at System.String.System.IConvertible.ToInt32(IFormatProvider provider)
   at System.Convert.ToInt32(Object value)
   at MySql.Data.Types.MySqlInt32.MySql.Data.Types.IMySqlValue.WriteValue(MySqlPacket packet, Boolean binary, Object val, Int32 length)
   at MySql.Data.MySqlClient.MySqlParameter.Serialize(MySqlPacket packet, Boolean binary, MySqlConnectionStringBuilder settings)
   at MySql.Data.MySqlClient.Statement.SerializeParameter(MySqlParameterCollection parameters, MySqlPacket packet, String parmName, Int32 parameterIndex)
   at MySql.Data.MySqlClient.Statement.InternalBindParameters(String sql, MySqlParameterCollection parameters, MySqlPacket packet)
   at MySql.Data.MySqlClient.Statement.BindParameters()
   at MySql.Data.MySqlClient.Statement.Execute()
   at MySql.Data.MySqlClient.PreparableStatement.Execute()
   at MySql.Data.MySqlClient.MySqlCommand.ExecuteReader(CommandBehavior behavior)
   at MySql.Data.MySqlClient.MySqlCommand.ExecuteReader()
   at MySql.Data.MySqlClient.MySqlCommand.ExecuteNonQuery()
   at log4net.Appender.AdoNetAppender.SendBuffer(IDbTransaction dbTran, LoggingEvent[] events)
   at log4net.Appender.AdoNetAppender.SendBuffer(LoggingEvent[] events)
zeParameter(MySqlParameterCollection parameters, MySqlPacket packet, String parmName, Int32 parameterIndex)
   at MySql.Data.MySqlClient.Statement.InternalBindParameters(String sql, MySqlParameterCollection parameters, MySqlPacket packet)
   at MySql.Data.MySqlClient.Statement.BindParameters()
   at MySql.Data.MySqlClient.Statement.Execute()
   at MySql.Data.MySqlClient.PreparableStatement.Execute()
   at MySql.Data.MySqlClient.MySqlCommand.ExecuteReader(CommandBehavior behavior)
   at MySql.Data.MySqlClient.MySqlCommand.ExecuteReader()
   at MySql.Data.MySqlClient.MySqlCommand.ExecuteNonQuery()
   at log4net.Appender.AdoNetAppender.SendBuffer(IDbTransaction dbTran, LoggingEvent[] events)
   at log4net.Appender.AdoNetAppender.SendBuffer(LoggingEvent[] events)

Seems like an issue with a value you're trying to insert. I think you have a column of NUMBER type. Can you post the value you're trying to insert for the column. Or better, values for all bind variables. — Rahul Vijay Dawda
Asking more directly, what are values of ?time, ?log_level, ?logger, ?message, ?exception, ?thread variables? — Rahul Vijay Dawda
These are all internal values of Log4Net. They are logged correctly to the database except for exception. — Z0q

Z0q Z0q · Accepted Answer · 2016-03-10T13:54:05

I found the error.

Apparently, I added some global variables which were not initialized yet when calling my test exception function. I initialized these variables to empty strings and zeroes and it worked.

Log4Net exception while writing exception to MySQL database

1 Answers