Question

我试图在sql查询中显示同一个表中的两个值。该表包含2个具有这些值的键。

目前，我做了这个

SELECT p.post_title, t.name, pm.meta_value AS address, pm.meta_value AS id
FROM `wp_posts` p
  LEFT JOIN wp_term_relationships trr ON p.ID = trr.object_id
  LEFT JOIN wp_term_taxonomy tax ON trr.term_taxonomy_id = tax.term_taxonomy_id
  LEFT JOIN wp_terms t ON tax.term_taxonomy_id = t.term_id
  LEFT JOIN wp_postmeta pm ON p.ID = pm.post_id
WHERE
  p.post_type = 'network-type' AND t.slug = 'atm' AND
  pm.meta_key IN ('network_address', 'network_branch_atm_id')

但是这显示了

| post_title | name | address   | id        |
---------------------------------------------
| Post name  | bla  | 12        | 12        |
| Post name  | bla  | address 1 | address 1 |

postmeta表格的值如下

| meta_id | post_id | meta_key              | meta_value |
----------------------------------------------------------
| 1212    | 323     | network_address       | address 1  |
| 1212    | 323     | network_branch_atm_id | 12         |

我尝试使用CASE但遇到了错误（用户不允许执行）。

我应该改变什么才能获得

| post_title | name | address   | id        |
---------------------------------------------
| Post name  | bla  | address 1 | 12        |

Answer 1

汇总帖子标题名称，然后转出地址和ID。您遇到的困难（以及我在wm_postmeta表中找到的）是将信息存储为键和值。它可能需要一些按摩来按照您希望的方式从Wordpress架构中提取数据。

SELECT
    p.post_title,
    t.name,
    MAX(CASE WHEN pm.meta_key = 'network_address'       THEN pm.meta_value END) AS address,
    MAX(CASE WHEN pm.meta_key = 'network_branch_atm_id' THEN pm.meta_value END) AS id
FROM wp_posts p
LEFT JOIN wp_term_relationships trr
    ON p.ID = trr.object_id
LEFT JOIN wp_term_taxonomy tax
    ON trr.term_taxonomy_id = tax.term_taxonomy_id
LEFT JOIN wp_terms t
    ON tax.term_taxonomy_id = t.term_id
LEFT JOIN wp_postmeta pm
    ON p.ID = pm.post_id
WHERE
    p.post_type = 'network-type' AND
    t.slug = 'atm' AND
    pm.meta_key IN ('network_address', 'network_branch_atm_id')
GROUP BY
    p.post_title,
    t.name;

从同一列中选择特定值并显示在不同的列中

1 个答案: