sql - 如何使用表中的数据作为 SQL 中键值的实体？

Question

我有一张如下表：

是否有任何 SELECT 查询以下列形式显示表格？

非常感谢。

标签： sqlselect

Answer 1

您可以尝试以下代码：

SELECT post_id,
       (SELECT meta_value from test where meta_key='_total') AS _total,
       (SELECT meta_value from test where meta_key='_phone') AS _phone,
       (SELECT meta_value from test where meta_key='_address') AS _address 
FROM test
GROUP BY post_id

更新 由于该表包含更多 post_id，请检查以下更新。

SELECT post_id,
       (SELECT meta_value from test t2 where meta_key='_total' AND t1.post_id=t2.post_id) AS _total,
       (SELECT meta_value from test t2 where meta_key='_phone' AND t1.post_id=t2.post_id) AS _phone,
       (SELECT meta_value from test t2 where meta_key='_address' AND t1.post_id=t2.post_id) AS _address
FROM test t1
GROUP BY post_id