title: to index or not in Oracle Exadata
body: <p>I am new to Oracle Exadata. My question is, <strong>to Index or not to Index in Exadata</strong>?</p>
  
  <p>Found some of the blogs which says not to Index database Index and only to storage indexes which are temporary, but there are no official documentation from Oracle which says not to index in Exadata.</p>
  
  <p>What are the issues if I index in Exadata? (since it is implemented in memory concepts), will it improve or downgrade performance? Is it better to drop index if already created?</p>
  
  <p>We have huge datas 15 million plus and growing in Oracle Exadata with Varchars, CLOBS and other common datatypes. Not having any indexes created except primary keys. Why query is taking 10 to 12 minutes ( from 15 million records with simple select query having few where conditions) for execution? Oracle says Exadata is the fastest database in the planet. </p>