How to write the back end code correctly for this procedure?

Part 1

From the above code, there are few points worth mentioning:

1. The method name "InsertCustomerEvaluation" doesn't provide much information about what the method does. A better name would be something like "CreateCustomerEvaluation" or "AddCustomerEvaluation".

2. It is important to validate the input parameter CUST_ID to ensure that it is not null or empty. If it is, then you should throw an exception or return an appropriate error message.

3. The code is not properly disposing the OracleParameter object C_E_ID. It's a good practice to use try-with-resources block to ensure that database resources are properly released.

4. If an exception occurs, the method returns -1. It would be better to return a boolean value indicating whether the operation was successful or not, and throw an exception if an error occurred.

5. Instead of just catching the exception and returning -1, it would be better to log the exception to a log file or a monitoring system, so that you can investigate the issue and fix the problem.
 

public int InsertCustomerEvaluation(string CUST_ID)
{
    OracleParameter C_E_ID = new OracleParameter("CEF_CE_ID", OracleDbType.Decimal);
    C_E_ID.Direction = ParameterDirection.Output;
    
    try
    {
        _context.Database.ExecuteSqlRaw(
            "BEGIN CEF_APP.InsertCustomerEvaluation(:CEF_CUST_ID, :CEF_CE_ID); END;",
            new OracleParameter("CEF_CUST_ID", CUST_ID),
            C_E_ID
        );
        
        return Convert.ToInt32(C_E_ID.Value);
    }
    catch (Exception e)
    {
        // handle the exception
    }
    
    return -1; // or throw an exception if needed
}