This error throws up whenever I enter a duplicate entry in mysql.

{ [Error: ER_DUP_ENTRY: Duplicate entry '[email protected]' for key 'email
'] code: 'ER_DUP_ENTRY', errno: 1062, sqlState: '23000', index: 0 }

What I want to do is turn this Error object into a string. I tried using JSON.stringify() and when I printed it on the console, only the last part got converted into a string :

{code:ER_DUP_ENTRY,errno:1062,sqlState:23000,index:0}

I need to convert the first part as well of the error, the one inside the [ ] so that I am able to diagnose duplicates properly. How do I retrieve that part whenever I convert an Error object into a string?