I used the following workaround to bypass this limitation:
- Wrap the function call using an anonymous block.
- Return an output variable containing 1 or 0.
- Read the output variable and cast it to boolean.
Here is some sample code:
using (var connection = new OracleConnection("<connection string>"))
{
var command = new OracleCommand();
command.Connection = connection;
command.CommandText =
"declare v_bool boolean;" +
"begin " +
"v_bool := auth_com.is_valid_username (:username); "+
"if (v_bool = TRUE) then select 1 into :v_result from dual; end if; " +
"if (v_bool = FALSE) then select 0 into :v_result from dual; end if; " +
"end;";
command.Parameters.Add(new OracleParameter { ParameterName = "username", OracleDbType = OracleDbType.NVarchar2, Size=512, Direction = ParameterDirection.Input });
command.Parameters.Add(new OracleParameter { ParameterName = "v_result", OracleDbType = OracleDbType.Decimal, Direction = ParameterDirection.Output });
try
{
connection.Open();
command.ExecuteNonQuery();
}
finally
{
connection.Close();
}
bool success = Convert.ToBoolean(((OracleDecimal)command.Parameters["v_result"].Value).ToInt32());
}
EDIT:
Alex Keh from Oracle, october 2013:
We're planning on supporting ODP.NET Boolean in the managed provider
in the near term, possibly in the middle of next year.
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