Postgres bytea column is returning string (char array) instead of byte array

Question

I have been using C# to write a concrete provider implementation for our product for different databases. W/out getting into details, one of the columns is of byte array typ

Answer 1

In Npgsql there is NpgsqlDataReader class to retrieve inserted rows, e.g:

NpgsqlConnection conn = new NpgsqlConnection(connStr);
conn.Open();

NpgsqlCommand insertCmd =
    new NpgsqlCommand("INSERT INTO binaryData (data) VALUES(:dataParam)", conn);
NpgsqlParameter param = new NpgsqlParameter("dataParam", NpgsqlDbType.Bytea);

byte[] inputBytes = BitConverter.GetBytes((int)0);
Console.Write("Input:");
foreach (byte b in inputBytes)
    Console.Write(" {0}", b);
Console.WriteLine();

param.Value = inputBytes;
insertCmd.Parameters.Add(param);
insertCmd.ExecuteNonQuery();

NpgsqlCommand selectCmd = new NpgsqlCommand("SELECT data FROM binaryData", conn);
NpgsqlDataReader dr = selectCmd.ExecuteReader();
if(dr.Read())
{
    Console.Write("Output:");
    byte[] result = (byte[])dr[0];
    foreach(byte b in result)
        Console.Write(" {0}", b);
    Console.WriteLine();
}

conn.Close();

Result from C# app:

Input: 0 0 0 0
Output: 0 0 0 0

Result from pgAdmin:

"\000\000\000\000"

EDIT:

I found explanation why you getting:

92 48 48 48 48 48 48 48 48

I checked my code with previous version Npgsql2.0.10-bin-ms.net3.5sp1.zip and get above result (of course pgAdmin returns \000\000\000\000), so I think that best what you can do is to use another version without this bug.

ANSWER: User higher version of Npgsql than 2.0.10