[Mono-devel-list] Npgsql - null reference exception during opening connection

Kamil Skalski nazgul at omega.pl
Sat May 15 06:47:20 EDT 2004

I've encountered an exception during opening of NpgsqlConnection. The stack 
trace is following:

sql.n:17:9: debug: System.NullReferenceException: A null value was found where 
an object instance was required.
in (unmanaged) /usr/lib/libmono.so.0(mono_class_from_name+0xd7) [0x4011c2a8]
in (unmanaged) /usr/lib/libmono.so.0 [0x400eb9a3]
in (unmanaged) /usr/lib/libmono.so.0 [0x400edbcf]
in (unmanaged) /usr/lib/libmono.so.0 [0x400ee2eb]
in <0x00066> System.Net.Dns:GetHostByName (string)
in <0x00032> System.Net.Sockets.TcpClient:Connect (string,int)
in <0x00026> System.Net.Sockets.TcpClient:.ctor (string,int)
in <0x00080> Npgsql.NpgsqlClosedState:Open (Npgsql.NpgsqlConnection)
in <0x00662> Npgsql.NpgsqlConnection:Open ()
in <0x0004f> (wrapper remoting-invoke-with-check) Npgsql.NpgsqlConnection:Open 

my connection string is
"Server=localhost;Database=test;User ID=postgres;Password=sql;"

The starngest thing is that I have another application, where exactly the same 
connection string succedes and I can query database without problem. I'm not 
yet able to find any related differences between those two application - 
there is no network / database specific code at all in them. 
I also tried Server= but the behavior is identical - I've one 
application succesfully opening connection and other failing.

I'm still trying to reproduce behavior in some small example, but maybe 
anybody has any suggestions? 

Kamil Skalski

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