MySQL 9.0 Release Notes
        
          Given a string argument, this function produces a quoted
          identifier suitable for inclusion in SQL statements. This is
          useful when a value to be used as an identifier is a reserved
          word or contains backtick (`) characters.
mysql> SELECT sys.quote_identifier('plain');
+-------------------------------+
| sys.quote_identifier('plain') |
+-------------------------------+
| `plain`                       |
+-------------------------------+
mysql> SELECT sys.quote_identifier('trick`ier');
+-----------------------------------+
| sys.quote_identifier('trick`ier') |
+-----------------------------------+
| `trick``ier`                      |
+-----------------------------------+
mysql> SELECT sys.quote_identifier('integer');
+---------------------------------+
| sys.quote_identifier('integer') |
+---------------------------------+
| `integer`                       |
+---------------------------------+