mysql數據庫對字段自定義排序的應用
阿新 • • 發佈：2018-10-22
cat mit lan 價格 pid life sans 函數 content
`welife_system`.`user_wechat`.`nickname`,
`quan_post_second`.`realname`,
`welife_system`.`user_wechat`.`avatar`,
`welife_system`.`user_wechat`.`has_auth`,
`welife_system`.`user_wechat`.`auth_info`,
`quan_post`.`type`,
`is_essence`,
`quan_post`.`title`,
`quan_post`.`content`,
`quan_post`.`num_view`,
`quan_post`.`create_at`
FROM
`welife_quan`.`quan_post`
LEFT JOIN `quan_topic` ON quan_topic.id = quan_post.topic_id
LEFT JOIN `welife_system`.`user_wechat` ON welife_system.user_wechat.unionid = welife_quan.quan_post.user_id
LEFT JOIN `quan_post_second` ON quan_post_second.pid = quan_post.id
LEFT JOIN `welife_center`.`city` ON welife_center.city.id = welife_quan.quan_post.city_id
WHERE
(`quan_post`.`type` = 1)
AND (`is_draft` = 0)
AND (
`quan_post_second`.`type` = ‘0‘
)
AND (`quan_post`.`status` = 1)
AND (`quan_post`.`status` != 3)
AND (`quan_post`.`status` != 2)
AND (`quan_post`.`status` != 4)
ORDER BY
FIELD(
quan_post_second.price,
- 1,
0
),
`quan_post_second`.`price`,
`quan_post`.`sort` DESC,
`quan_post`.`last_comment_time` DESC,
`quan_post`.`create_at` DESC
LIMIT 30
之前做項目 有個需求是
二手租房按照 房租價格 從低到高排序，面議的價格要在最後顯示出來。
因為數據庫中 面議 的價格(price)是（-1,0）
如果按照從低到高，面議的價格就會顯示在最前面了，這不是項目需求要的。
所以要寫一個自定義的排序。
MySQL 中 field自定義排序函數的格式
order by field(value,str1,str2,str3,str4,,,,,,strn)
其中value後面的參數自定義，不限制參數個數
含義
將獲取出來的數據根據str1,str2,str3,str4等的順序排序
--------------------------------------------------------------------------------------------------
SELECT
`quan_post`.`id`,
`quan_post`.`is_large`,
`welife_center`.`city`.`name` AS `city_name`,
`level_id`,
`cate_id`,
`quan_topic`.`title` AS `topic_title`,
`quan_post_second`.`img_list`,
`price_market`,
`quan_post_second`.`type` AS `second_type`,
`price`,
`quan_post`.`anony`,
`welife_system`.`user_wechat`.`sex`,
`welife_system`.`user_wechat`.`nickname`,
`quan_post_second`.`realname`,
`welife_system`.`user_wechat`.`avatar`,
`welife_system`.`user_wechat`.`has_auth`,
`welife_system`.`user_wechat`.`auth_info`,
`quan_post`.`type`,
`is_essence`,
`quan_post`.`title`,
`quan_post`.`content`,
`quan_post`.`num_view`,
`quan_post`.`create_at`
FROM
`welife_quan`.`quan_post`
LEFT JOIN `quan_topic` ON quan_topic.id = quan_post.topic_id
LEFT JOIN `welife_system`.`user_wechat` ON welife_system.user_wechat.unionid = welife_quan.quan_post.user_id
LEFT JOIN `quan_post_second` ON quan_post_second.pid = quan_post.id
LEFT JOIN `welife_center`.`city` ON welife_center.city.id = welife_quan.quan_post.city_id
WHERE
(`quan_post`.`type` = 1)
AND (`is_draft` = 0)
AND (
`quan_post_second`.`type` = ‘0‘
)
AND (`quan_post`.`status` = 1)
AND (`quan_post`.`status` != 3)
AND (`quan_post`.`status` != 2)
AND (`quan_post`.`status` != 4)
ORDER BY
FIELD(
quan_post_second.price,
- 1,
0
),
`quan_post_second`.`price`,
`quan_post`.`sort` DESC,
`quan_post`.`last_comment_time` DESC,
`quan_post`.`create_at` DESC
LIMIT 30
mysql數據庫對字段自定義排序的應用