如何检索列和其他变量中具有相同ID和相同值的两行。这是“数据”表
+----- ------+-----------------+------------------+
| post_id | meta_key | meta_value |
+----- ------+-----------------+------------------+
| 1000 | payment_method | visa |
| 1000 | other | sometext |
| 1000 | order_total | 65.00 |
| 1000 | etc | sometext2 |
| 1001 | payment_method | bacs |
| 1001 | other | sometext |
| 1001 | order_total | 105.00 |
| 1001 | etc | sometext2 |
| 1002 | payment_method | visa |
| 1002 | other | sometext |
| 1002 | order_total | 28.00 |
| 1002 | etc | sometext2 |
| ... | ... | ... |
+------------+-----------------+------------------+
如您所见,付款方式有稳定的价值,订单总额是可变的。
我试过:
从meta_key in('付款方式')的'data'中选择*,
'order_total')按post_id、meta_key分组
输出
+----- ------+-----------------+------------------+
| post_id | meta_key | meta_value |
+----- ------+-----------------+------------------+
| 1000 | payment_method | visa |
| 1000 | order_total | 65.00 |
| 1001 | payment_method | bacs |
| 1001 | order_total | 105.00 |
| 1002 | payment_method | visa |
| 1002 | order_total | 28.00 |
| ... | ... | ... |
+------------+-----------------+------------------+
我只想要支付方式=签证和他各自的邮资。
+----- ------+-----------------+------------------+
| post_id | meta_key | meta_value |
+----- ------+-----------------+------------------+
| 1000 | payment_method | visa |
| 1000 | order_total | 65.00 |
| 1002 | payment_method | visa |
| 1002 | order_total | 28.00 |
| ... | ... | ... |
+------------+-----------------+------------------+
谢谢您。
