title: Is quote REQUIRED in calcite sql parser?
body: <p>From the config there is a few options, of <code>\"</code>, <code>[</code> etc. </p>
  
  <p>However is it possible for calcite to parse identifiers without quotes? like </p>
  
  <p><code>select * from a.b</code>? </p>
  
  <p>Now I must write </p>
  
  <p><code>select * from \"a\".\"b\"</code> </p>
  
  <p>and it's kind of annoying. </p>