title: DBExpress: How to find a primary key field?
body: <p>I have a TSimpleDataSet based on dinamically created SQL query. I need to know which field is a primary key?</p>
  
  <pre><code>SimpleDataSet1.DataSet.SetSchemaInfo(stIndexes, 'myTable' ,'');
  </code></pre>
  
  <p>This code tells me that i have a primary key with name 'someName', but how can i know which field (column) works with this index?</p>