mysql 5.7 json_extract，带有产品表中所有结果的键

Question

我需要通过json字段功能过滤产品：

id | name_product | features|

现场特点：

[{
    "en": "System Operation",
    "it": "Sistema operativo",
    "value": "IOS 8"
}, {
    "en": "Memory Ram",
    "it": "Memoria Ram",
    "value": "16 Gb"
}, {
    "en": "display",
    "it": "schermo",
    "value": "5.5\""
}]

有些产品有一些共同的功能，对于过滤器，我试试这个：

SELECT * FROM products WHERE json_extract(features,'$[*].value') = "IOS 8";

和：

SELECT * FROM products WHERE 'IOS 8' = json_extract(features,'$[*].value');

但结果是一样的：NULL
如果我将位置放在数组而不是*：

SELECT * FROM products WHERE json_extract(feature,'$[1].value') = "IOS 8";

我有结果，问题是：我不知道究竟在哪里。 在某些产品中， $[1].value在其他产品中is $[2].value在其他产品中$[10].value
$[*].value是最好的但是为null :(
怎么解决这个问题？
谢谢！！

Answer 1

尝试：

mysql> DROP TABLE IF EXISTS `products`;
Query OK, 0 rows affected (0.18 sec)

mysql> CREATE TABLE IF NOT EXISTS `products`(
    ->   `id` INT UNSIGNED NOT NULL AUTO_INCREMENT,
    ->   `name_product` VARCHAR(50),
    ->   `features` JSON,
    ->   PRIMARY KEY (`id`)
    -> );
Query OK, 0 rows affected (0.24 sec)

mysql> INSERT INTO `products`
    ->     (`name_product`, `features`)
    -> VALUES
    ->     ('product 1',
    ->      '[
    '>        {"en": "System Operation", "it": "Sistema operativo", "value": "IOS 8"},
    '>        {"en": "Memory Ram", "it": "Memoria Ram", "value": "16 Gb"},
    '>        {"en": "display", "it": "schermo", "value": "5.5\'\'"}
    '>      ]'),
    ->      ('product 2',
    ->      '[
    '>        {"en": "System Operation", "it": "Sistema operativo", "value": "IOS 7"},
    '>        {"en": "Memory Ram", "it": "Memoria Ram", "value": "16 Gb"},
    '>        {"en": "display", "it": "schermo", "value": "5.5\'\'"}
    '>      ]'),
    ->      ('product 3',
    ->      '[
    '>        {"en": "Memory Ram", "it": "Memoria Ram", "value": "16 Gb"},
    '>        {"en": "display", "it": "schermo", "value": "5.5\'\'"},
    '>        {"en": "System Operation", "it": "Sistema operativo", "value": "IOS 8"}
    '>      ]');
Query OK, 3 rows affected (0.05 sec)
Records: 3  Duplicates: 0  Warnings: 0

mysql> SELECT `id`, `name_product`, `features`
    -> FROM `products`
    -> WHERE JSON_SEARCH(`features`, 'all', 'IOS 8', NULL, '$[*].value') IS NOT NULL;
+----+--------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| id | name_product | features                                                                                                                                                                                     |
+----+--------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
|  1 | product 1    | [{"en": "System Operation", "it": "Sistema operativo", "value": "IOS 8"}, {"en": "Memory Ram", "it": "Memoria Ram", "value": "16 Gb"}, {"en": "display", "it": "schermo", "value": "5.5''"}] |
|  3 | product 3    | [{"en": "Memory Ram", "it": "Memoria Ram", "value": "16 Gb"}, {"en": "display", "it": "schermo", "value": "5.5''"}, {"en": "System Operation", "it": "Sistema operativo", "value": "IOS 8"}] |
+----+--------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
2 rows in set (0.00 sec)