title: "Where clause" is not working in AWS Athena
body: <p><a href="https://i.stack.imgur.com/mYFH7.png" rel="noreferrer"><img src="https://i.stack.imgur.com/mYFH7.png" alt="data sample"></a></p>
  
  <p>I used AWS Glue Console to create a table from S3 bucket in Athena. You can see a relevant part on the screenshot above. I obfuscated column name, so assume the column name is <code>"a test column"</code>. I would like to select the records with value <strong>D</strong> in that column. The query I tried to run is:</p>
  
  <pre class="lang-sql prettyprint-override"><code>SELECT 
      * 
  FROM 
      table 
  WHERE 
      "a test column" = "D"
  </code></pre>
  
  <p>Nothing is returned. I also tried to use <strong>IS</strong> instead of <strong>=</strong>, as well as to surround <strong>D</strong> with single quotes instead of double quotes within the <code>WHERE</code> clause:</p>
  
  <pre class="lang-sql prettyprint-override"><code>-- Tried this
  WHERE 
      "a test column" = 'D'
  
  -- Tried this
  WHERE 
      "a test column" IS "D"
  
  -- Tried this
  WHERE 
      "a test column" IS 'D'
  </code></pre>
  
  <p>Nothing works. Can someone help? Thank you.</p>
  
  <p>The error message I got is </p>
  
  <blockquote>
    <p>Mismatched input 'where' expecting  (service: amazon athena; status code: 400; error code: invalid request exception; request id: 8f2f7c17-8832-4e34-8fb2-a78855e3c17d) </p>
  </blockquote>