实现数据库驱动查询功能示例

对于数据库驱动提供者，此处给出实现查询功能的样例代码：

public class Rows <: QueryResult {
    public func next(values: Array<SqlDbType>): Bool {
        for (idx in 0..values.size) {
            match (values[idx]) {
                case v: SqlBigInt => v.value = 100
                case v: SqlVarchar => v.value = "foo"
                case v: SqlNullableTimestamp => v.value = None
                case v: MySqlExtXmlType => v.value = "<element></element>"
                case _ => ()
            }
        }
        return false
    }
}