solidity 2 nested mapping

add a book

get book based on publisher -> id

//mycontract.sol

pragma solidity ^0.6.0;

contract MyContract {

    mapping(address => mapping(uint => Book)) public myBooks;

    

    struct Book{

        string title;

        string author;

    }

    

    function addMyBook(uint _id, string memory _title, string memory _author) public {

        myBooks[msg.sender][_id] = Book(_title, _author);

    }

}

reference:

https://www.youtube.com/watch?v=YJ-D1RMI0T0