d with backticks.
             Parameters
             in_identifier (TEXT):
               The identifier to quote.
             Returns
             TEXT
             Example
             mysql> SELECT sys.quote_identifier('my_identifier') AS Identifier;
             +-----------------+
             | Identifier      |
             +-----------------+
             | `my_identifier` |
             +-----------------+
             1 row in set (0.00 sec)
             mysql> SELECT sys.quote_identifier('my`idenfier') AS Identifier;
             +----------------+
             | Identifier     |
             +----------------+
             | `my``idenfier` |
             +----------------+
             1 row in set (0.00 sec)
            BEGIN
    RETURN CONCAT('`', REPLACE(in_identifier, '`', '``'), '`');
END