使用 Dapper (C#) 调用 PostgreSQL 存储过程

Question

I'm posting this for two reasons

1. I'm new to PostgreSQL and it took a while to piece this information together, so I thought someone else would find this helpful and
2. to ask if there is another way to call a PostgreSQL stored procedure that doesn't require all of the parameters to be included in the stored procedure name/signature.

The following uses Dapper and Npgsql to make a call to a PostgreSQL stored procedure that inserts (null id_inout passed in) or updates a record (id_inout has a value).

I'd like to understand why PostgreSQL requires the entire stored procedure signature when making the call.

    public static int? PO_Save(PurchaseOrder po)
    {

        int? recordId = null;           

        using (var cn = new NpgsqlConnection(AppSettings.ConnectionString))
        {
            if (cn.State != ConnectionState.Open)
                cn.Open();

            var procName = "CALL po_save(@in_ponumber,@in_deliverydate,@in_bldnum," +
                "@in_facname,@in_facnumber,@in_facaddress1,@in_facaddress2,@in_city," +
                "@in_state,@in_zip,@in_theme,@id_inout)";
            var p = new Dapper.DynamicParameters();
            p.Add("@in_ponumber", po.PONumber);
            p.Add("@in_deliverydate", po.DeliveryDate);
            p.Add("@in_bldnum", po.BldNum);
            p.Add("@in_facname", po.FacName);
            p.Add("@in_facnumber", po.FacNumber);
            p.Add("@in_facaddress1", po.FacAddress1);
            p.Add("@in_facaddress2", po.FacAddress2);
            p.Add("@in_city", po.City);
            p.Add("@in_state", po.State);
            p.Add("@in_zip", po.Zip);
            p.Add("@in_theme", po.Theme);
            p.Add("@id_out", po.POID, null, ParameterDirection.InputOutput);
            var res = cn.Execute(procName, p);
            recordId = p.Get<int>("@id_inout");
        }

        return recordId;
    }

Answer 1

You should be able to pass commandType: CommandType.StoredProcedure to Execute , eg:

var res = cn.Execute(
    "po_save",
    new {
        in_ponumber = po.PONumber,
        in_deliverydate = po.DeliveryDate,
        // etc...
    },
    commandType: CommandType.StoredProcedure,
);

Here's the docs with such an example: https://github.com/StackExchange/Dapper/blob/main/Readme.md#stored-procedures