title: Why does the REGEXP_LIKE function treat the letter 'e' as upper case instead of lower case?
body: <p>In my pl/sql script Oracle treats the letter 'e' as upper case when searching by the [:upper:] Character Class Syntax.</p>
  
  <p>i.e.</p>
  
  <pre><code>REGEXP_LIKE('e', '[:upper:]')
  
  REGEXP_LIKE('e', '[:lower:]')
  </code></pre>
  
  <p>Related Oracle docs can be found here:</p>
  
  <p><a href="http://docs.oracle.com/cd/B14117_01/server.101/b10759/ap_posix001.htm#i690819" rel="nofollow">Oracle - Multilingual Regular Expression Syntax</a></p>
  
  <p><a href="http://docs.oracle.com/cd/B14117_01/server.101/b10759/conditions018.htm" rel="nofollow">Oracle - REGEXP_LIKE</a></p>