我有產(chǎn)品價(jià)格的歷史列表（按created_at排序），如下所示：Array( [0] => stdClass Object ( [id] => 1 [product_id] => 49 [price] => 14520000.0000 [created_at] => 1592501154 ) [1] => stdClass Object ( [id] => 2 [product_id] => 49 [price] => 14000000.0000 [created_at] => 1592587554 ) [2] => stdClass Object ( [id] => 4 [product_id] => 49 [price] => 14800000.0000 [created_at] => 1592673954 ) [3] => stdClass Object ( [id] => 5 [product_id] => 49 [price] => 10000000.0000 [created_at] => 1592760354 ) [4] => stdClass Object ( [id] => 6 [product_id] => 49 [price] => 14000000.0000 [created_at] => 1592846754 ) [5] => stdClass Object ( [id] => 7 [product_id] => 49 [price] => 14000000.0000 [created_at] => 1592933154 ) [6] => stdClass Object ( [id] => 8 [product_id] => 49 [price] => 14000000.0000 [created_at] => 1593019554 ))現(xiàn)在，為了在表中顯示數(shù)據(jù)，我使用foreach如下方法列出了價(jià)格： <?php foreach($product_prices_list as $product_price_list):?> <tr> <td><?= esc($product_price_list->created_at);?></td> <td class="text-center"><?= esc(number_format($product_price_list->price));?></td> <td class="text-center"></td> //show difference between of two price </tr> <?php endforeach;?>我可以在表中看到真實(shí)的輸出，但我需要在第三列中顯示兩個(gè)價(jià)格之間的差異，如下圖所示：我如何顯示列表中兩個(gè)價(jià)格之間的差異？！
2 回答
ITMISS
TA貢獻(xiàn)1871條經(jīng)驗(yàn) 獲得超8個(gè)贊
您只需將當(dāng)前價(jià)格屬性與數(shù)組中前一個(gè)對(duì)象的價(jià)格進(jìn)行比較？
像這樣的東西應(yīng)該有效：
<?php foreach($product_prices_list as $key => $product_price_list):?>
<tr>
<td><?= esc($product_price_list->created_at);?></td>
<td class="text-center"><?= esc(number_format($product_price_list->price));?></td>
<td class="text-center"><?= (!empty($product_prices_list[$key - 1])) ? $product_prices_list[$key + 1]->price - $product_price_list->price: 0; ?></td> //show difference between of two price
</tr>
<?php endforeach;?>
慕田峪4524236
TA貢獻(xiàn)1875條經(jīng)驗(yàn) 獲得超5個(gè)贊
如果您運(yùn)行的是 MySQL 8.0，則可以使用窗口函數(shù)直接在數(shù)據(jù)庫(kù)中計(jì)算此信息：
select
t.*,
price
- lag(price, 1, price) over(partition by product_id order by created_at)
as price_diff
from mytable t
這會(huì)向結(jié)果集中再添加一列，其中包含同一產(chǎn)品的當(dāng)前價(jià)格與之前價(jià)格之間的差異。
- 2 回答
- 0 關(guān)注
- 194 瀏覽
添加回答
舉報(bào)
0/150
提交
取消