Npgsql exception when connecting

Question

I am using the Npgsql 2.0.11.94 in a C# .NET 4.0 application to connect to a PostgreSql database. I have formed the connection string according to the example on their website, and when I call connect with the NpgsqlConnection object, this exception is thrown:

A first chance exception of type 'Npgsql.NpgsqlException' occurred in Npgsql.dll

Additional information: ERROR: 22023: 3 is outside the valid range for parameter "extra_float_digits" (-15 .. 2)

The code will execute correctly after the exception is thrown. That is, the connection to the database does get established and the queries return the correct data. Does anyone know why it's throwing this exception? Here is my code to connect to the db:

string strConnection = "Server=192.168.253.20;Port=5432;User Id=alex;Password=asdf;Database=mydatabase;";
NpgsqlConnection conn = null;
try
{
    conn = new NpgsqlConnection(strConnection);
    conn.Open();
}
catch (Exception e)
{
}

Any help would be much appreciated.

Thanks, Alex

Answer 1

It's a bug with the initial set-up upon establishing a connection.

There are a few different commands that get carried out on every connection that is first opened (but not repeatedly when pooled connections are re-used), and this one is at attempt to deal with the different degrees of precision allowed with floating-number formatting between different versions of PostgreSQL.

Clearly it's not going quite as planned.

Taking a quick look at the source, it seems that the call is wrapped and should eat any such exception, but maybe that's after the last release. If so, then building from source may solve your problem.

Or you could go back a version, or just wrap with a try-catch until the next release.