title: MySQL JSON_EXTRACT path expression error
body: <p>The syntax looks right to me, any help would be appreciated!</p>
  
  <pre><code>mysql&gt; select fieldnames from tablename limit 5;
  +--------------------------------------------------------+
  | fieldnames                                             |
  +--------------------------------------------------------+
  | {"example-field-1": "val2"}                            |
  | {"example-field-2": "val1"}                            |
  | {"example-field-1": "val1", "example-field-3": "val1"} |
  | {"example-field-2": "val1"}                            |
  | {"example-field-2": "val2"}                            |
  +--------------------------------------------------------+
  mysql&gt; select JSON_EXTRACT(fieldnames, '$.example-field-1') from tablename;
  ERROR 3143 (42000): Invalid JSON path expression. The error is around character position 17 in '$.example-field-1'.
  </code></pre>
  
  <p>MySQL 5.7.10</p>