如何删除 MySQL 的 JSON 列中的键

Question

我的数据很脏，现在我正在尝试纠正它们。

数据是这样的：

mysql> select attrs from goods  limit 10;
+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| attrs                                                                                                                                                                                                                                                                    |
+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| {"logo": "1", "cover": "", "level": 0, "tag_6": 8, "summary": "L1", "showStatus": 0, "classAmount": 0, "productType": 0, "courseEndTime": 1532572800000, "courseStartTime": 1531706400000}  |
| {"logo": "1", "cover": "", "level": 0, "tag_6": 8, "summary": "L1", "showStatus": 0, "classAmount": 0, "productType": 0, "courseEndTime": 1533717600000, "courseStartTime": 1532851200000}  |
| {"logo": "1", "cover": "", "level": 0, "tag_6": 8, "summary": "L1", "showStatus": 0, "classAmount": 0, "productType": 0, "courseEndTime": 1534851600000, "courseStartTime": 1533985200000}  |
| {"logo": "1", "cover": "", "level": 0, "tag_6": 8, "summary": "L2", "showStatus": 0, "classAmount": 0, "productType": 0, "courseEndTime": 1532594400000, "courseStartTime": 1531728000000}  |
| {"logo": "1", "cover": "", "level": 0, "tag_147": 8, "tag_145": 2 "summary": "L2", "showStatus": 0, "classAmount": 0, "productType": 0, "courseEndTime": 1533728400000, "courseStartTime": 1532862000000}  |
| {"logo": "1", "cover": "", "level": 0, "tag_6": 8, "summary": "L2", "showStatus": 0, "classAmount": 0, "productType": 0, "courseEndTime": 1534819200000, "courseStartTime": 1533952800000}  |
| {"logo": "1", "cover": "", "level": 0, "tag_127": 8, "summary": "NGL", "showStatus": 0, "classAmount": 0, "productType": 0, "courseEndTime": 1532605200000, "courseStartTime": 1531738800000} |
| {"logo": "1", "cover": "", "level": 0, "tag_6": 8, "summary": "NGL", "showStatus": 0, "classAmount": 0, "productType": 0, "courseEndTime": 1533696000000, "courseStartTime": 1532829600000} |
|
+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+

如果这些对中的任何一个存在(key, value)我想删除列attrs中的一些(key, value)对。 例如tag_147和tag_124是脏的，那么任何命中对都将被删除。

{"tag_147": 1, "tag_124": 2}  ===>  {}
{"tag_147": 1 "tag_100":2}  ==>  {"tag_100": 2}

我怎样才能实现它？ 谢谢。

我尝试过的是 1. 找到包含键tag_147和tag_124 attrs 。 2. 然后更新 attrs。 我原来的 Sql 是这样的：

update goods
set json_remove(*XXX*) 
where (select json_keys(attrs) from goods ) contains  (*tag_147*, *tag_127*)

在这里，我被构造contains语句阻止了......

Answer 1

如果你只是想删除来自这两个标签attrs同时包含他们的价值观，你可以使用JSON_REMOVE任何attrs通过发现价值JSON_CONTAINS_PATH ，使用all的模式JSON_CONTAINS_PATH只找到其中包含这两个标签值：

UPDATE goods
SET attrs = JSON_REMOVE(attrs, '$.tag_147', '$.tag_124')
WHERE JSON_CONTAINS_PATH(attrs, 'all', '$.tag_147', '$.tag_124')

如果要完全删除attrs值包含两个标签的行，可以在DELETE查询中使用相同的JSON_CONTAINS_PATH条件：

DELETE
FROM goods
WHERE JSON_CONTAINS_PATH(attrs, 'all', '$.tag_147', '$.tag_124')

dbfiddle 上的演示

如果您想从包含其中任何一个的attrs值中删除这些标签，您可以删除UPDATE中的WHERE子句，即

UPDATE goods
SET attrs = JSON_REMOVE(attrs, '$.tag_147', '$.tag_145')

要删除attrs值包含任何标签的行，请将all参数更改为JSON_CONTAINS_PATH为one ：

DELETE
FROM goods
WHERE JSON_CONTAINS_PATH(attrs, 'one', '$.tag_147', '$.tag_145')

dbfiddle 上的演示