/// <summary>
/// Given a store datareader, a column name, find the column ordinal
/// in the datareader with the name of the column.
///
/// We only have the functionImport provided to include it in the exception
/// message.
/// </summary>
/// <param name="storeDataReader"></param>
/// <param name="columnName"></param>
/// <param name="functionImport"></param>
/// <returns></returns>
private static int GetDiscriminatorOrdinalFromReader(DbDataReader storeDataReader, string columnName, EdmFunction functionImport)
{
int result;
if (!TryGetColumnOrdinalFromReader(storeDataReader, columnName, out result))
{
throw EntityUtil.CommandExecutionDataReaderMissinDiscriminatorColumn(columnName, functionImport);
}
return(result);
}