Json problem obtained from the database-php Tutorial

I saved a piece of JOSN code in a field in the data inventory, but the double quotation marks were escaped after the code was saved.
Like This

[{& Quot; id & quot;: & quot; 9 & quot;, & quot; model & quot;: & quot; A2 & quot;, & quot; quantity & quot;: 1}]

It is also displayed in html without quotation marks.
How can I convert it into json code.

Reply to discussion (solution)

[{"Id": "9", "model": "A2", "quantity": 1 },{ "id": "8", "model ": "A1", "quantity": 1}]

It should have been like this.

$ S = '[{& quot; id & quot;: & quot; 9 & quot;, & quot; model & quot;: & quot; A2 & quot ;, & quot; quantity & quot;: 1}] '; echo html_entity_decode ($ s ));

[{"Id": "9", "model": "A2", "quantity": 1}]

When you import data to the database, you perform htmlentities encoding conversion. Naturally, you cannot directly use it.