title: Athena shows no value against boolean column, table created using glue crawler
body: <p>I am using aws glue csv crawler to crawl s3 directory containing csv files. Crawler works fine in the sense that it creates the schema with correct data types for each column, however, when I query data from athena, it doesn't show value under boolean type column.</p>
  
  <p>A csv looks like this:</p>
  
  <pre><code>"val","ts","cond"
  "1.2841974","15/05/2017 15:31:59","True"
  "0.556974","15/05/2017 15:40:59","True"
  "1.654111","15/05/2017 15:41:59","True"
  </code></pre>
  
  <p>And the table created by crawler is:</p>
  
  <pre><code>Column name Data type
  val         string
  ts          string
  cond        boolean
  </code></pre>
  
  <p>However, when I run say <code>select * from &lt;table_name&gt; limit 10</code> it returns:</p>
  
  <pre><code>    val         ts                      cond
  1   "1.2841974" "15/05/2017 15:31:59"   
  2   "0.556974"  "15/05/2017 15:40:59"   
  3   "1.654111"  "15/05/2017 15:41:59"   
  </code></pre>
  
  <p>Does any one has any idea what might be the reason?</p>
  
  <p>I forgot to add, if I change the data type of <code>cond</code> column to <code>string</code>, it does show data as string e.g. <code>"True"</code> or <code>"False"</code></p>