How To Use ODAC With Visual Studio 2015 Call Oracle DB (Stored-Function) - oracle

Question

There is a strange problem that has been found in Oracle DB with Visual Studio by my project. First I open my Toad to check Oracle function like as below picture:
When I have put 3 parameter's value into SF_GET_COMP_SVAL, it is working ,and then when I have tried it in my project as following, it also works very well.
using (OracleConnection con = new OracleConnection(ConfigurationManager.ConnectionStrings["OracleDbContext"].ToString()))
{
using (OracleCommand cmd = new OracleCommand())
{
cmd.CommandText = "select PG_AIS.SF_GET_COMP_SVAL('3','2','1') from dual";
try
{
cmd.Connection = con;
con.Open();
cmd.ExecuteNonQuery();
}
catch
{
}
}
}
However it can't be working when I use Paramters mode like as following code
cmd.CommandText="select PG_AIS.SF_GET_COMP_SVAL(:a1,:a2,:a3) from dual"; cmd.Parameters.Add("a2", "1");
cmd.Parameters.Add("a3", "2");
cmd.Parameters.Add("a1", "3");
why????

Answer 1

I wasted half day and have found the ODAC problem in my case, why can't insert into data with paramters in Visual Studio platform , because of parameters name , if fact in my MySql and MSSql there don't need to follow the sequence with parameter , but unfortunately in the Oracle it can't change ordering ,the parameter's depends on index sequence so that you can change any parameter's name
cmd.CommandText="select PG_AIS.SF_GET_COMP_SVAL(:a1,:a2,:a3) from dual";
cmd.Parameters.Add("a1", "3");
cmd.Parameters.Add("a2", "2");
cmd.Parameters.Add("a3", "1");
or
cmd.CommandText="select PG_AIS.SF_GET_COMP_SVAL(:a1,:a2,:a3) from dual";
cmd.Parameters.Add("xx", "3");
cmd.Parameters.Add("a2", "2");
cmd.Parameters.Add("a3", "1");
parameter a1 or xx is the same (depends on index sequence not parameter name)
both codes can get the same result.
PS: Hopefully it will be modify soon by Oracle Provider.

Answer 2

I have found another method to deal with this problem , please try it
OracleCommand command = new OracleCommand(query, connection)
{ CommandType = CommandType.Text, BindByName = true };
PS:http://www.codeproject.com/Articles/208176/Gotcha-sharp-Using-Named-Parameters-with-Oracl <-- it could be a great way to deal with