Question

说，我在MySQL上有一个名为tbl_order的表，结构如下（只是插图）：

---------------------------------------------------------------------------------------------------------
| id | grade | type  | order_date          | order_confim_time   | vol_in | vol_out | vol_dev | status  |
| AI | VARCH | VARCH | TIMESTAMP           | TIMESTAMP           | DOUBLE | DOUBLE  | DOUBLE  | VARCH   |
---------------------------------------------------------------------------------------------------------
| 81 | AAA   | IN    | 2014-09-10 09:00:00 | 2014-09-10 13:00:00 | 498000 |       0 |   -2000 | CONFIRM |
| 83 | AAA   | IN    | 2014-09-10 10:01:00 | 2014-09-10 14:00:00 | 998000 |       0 |   -2000 | CONFIRM |
| 85 | AAA   | OUT   | 2014-09-11 09:02:00 | 2014-09-11 13:00:00 |      0 |   99000 |   -1000 | CONFIRM |
| 87 | AAA   | OUT   | 2014-09-11 10:03:00 | 2014-09-11 14:00:00 |      0 |  145000 |   -5000 | CONFIRM |
| 89 | AAA   | OUT   | 2014-09-12 09:04:00 | 2014-09-12 13:00:00 |      0 |  120000 |   -5000 | CONFIRM |
| 91 | AAA   | OUT   | 2014-09-12 09:06:00 | NULL                |      0 |  130000 |   -2000 | NOTCONF |
| 93 | AAA   | OUT   | 2014-09-13 10:05:00 | 2014-09-12 14:00:00 |      0 |  115000 |   -5000 | CONFIRM |
---------------------------------------------------------------------------------------------------------

然后我做了以下查询：

SELECT * FROM `tbl_order` WHERE `tbl_order`.`grade` = 'AAA' AND `tbl_order`.`order_confim_time` < NOW() ORDER BY `tbl_order`.`status` DESC, `tbl_order`.`order_confim_time` ASC

这样我们就可以获得以下结果：

---------------------------------------------------------------------------------------------------------
| id | grade | type  | order_date          | order_confim_time   | vol_in | vol_out | vol_dev | status  |
| AI | VARCH | VARCH | TIMESTAMP           | TIMESTAMP           | DOUBLE | DOUBLE  | DOUBLE  | VARCH   |
---------------------------------------------------------------------------------------------------------
| 91 | AAA   | OUT   | 2014-09-12 09:06:00 | NULL                |      0 |  130000 |   -2000 | NOTCONF |
| 93 | AAA   | OUT   | 2014-09-13 10:05:00 | 2014-09-12 14:00:00 |      0 |  115000 |   -5000 | CONFIRM |
| 89 | AAA   | OUT   | 2014-09-12 09:04:00 | 2014-09-12 13:00:00 |      0 |  120000 |   -5000 | CONFIRM |
| 87 | AAA   | OUT   | 2014-09-11 10:03:00 | 2014-09-11 14:00:00 |      0 |  145000 |   -5000 | CONFIRM |
| 85 | AAA   | OUT   | 2014-09-11 09:02:00 | 2014-09-11 13:00:00 |      0 |   99000 |   -1000 | CONFIRM |
| 83 | AAA   | IN    | 2014-09-10 10:01:00 | 2014-09-10 14:00:00 | 998000 |       0 |   -2000 | CONFIRM |
| 81 | AAA   | IN    | 2014-09-10 09:00:00 | 2014-09-10 13:00:00 | 498000 |       0 |   -2000 | CONFIRM |
---------------------------------------------------------------------------------------------------------

我在模型Order中编写了以下函数，以便使用递归获取上一行：


    // i made simplify code, but still the code only work on 1st previous row. the rest still not.
    public function getPrevRow() {
    if (is_null($this->order_confim_time))
        {
            $data = self::model()->find(array(
                'condition' => '`t`.`grade`=:type_order AND (`t`.`order_date` '`t`.`status` DESC, `t`.`order_confim_time` DESC, `t`.`id` DESC',
                'limit'     => 1,
                'params'    => array('type_order' => $this->grade, ':current_date_confirm' => $this->order_confim_time),
            ));

            if (is_null($data)) return 0;
            else return floatval($data->PrevRow) +
            floatval($data->vol_in) +
            floatval($data->vol_dev) -
            floatval($data->vol_out);
        } else {
            $data = self::model()->find(array(
                'condition' => '`t`.`order_confim_time` '`t`.`status` DESC, `t`.`id` DESC',
                'limit'     => 1,
                'params'    => array(':current_date_confirm' => $this->order_confim_time, 'type_order' => $this->grade),
            ));

            if (is_null($data)) return 0;
            else return floatval($data->PrevRow) +
            floatval($data->vol_in) +
            floatval($data->vol_dev) -
            floatval($data->vol_out);
        }
    }

结果非常好，仅尊重order_confirm_time NOT NULL值。

Current result in CGridView

The expected condition is something like this

如何在不需要依赖ORDER BY id DESC的情况下获取上一行？目前我依赖于ORDER BY order_confirm_time。

我正在使用YII 1.1.16-branch，php 5.4 @ Windows 7 x64，MariaDB 5.5.38

Answer 1

在伪代码中，你可以这样做：

初始化tempv_var
初始化my_array
循环你的记录
在将记录传递给my_array
my_array [temp_var]
增量temp_var

最后，您的my_array内容记录的索引为temp_var。这是直接的解决方案，但您可以在SQL查询中执行此操作并在脚本上添加一些逻辑。

如何选择以前的记录不依赖于MySQL中的AutoIncrements ID？

1 个答案: