title: Larger clustered index vs more non clustered indexes
body: <p>To give a bit of background, we have a Kimball led Dimensional model star schema with a couple of Measures and Dimensions. We have 2 big Measure tables consisting of about 4 billion rows each, one measure and about 8 keys to dimensions.  </p>
  
  <p>So as far as I know, the wider an index the slower it is (number of levels?), same for non-clustered as well as clustered.</p>
  
  <p>I understand that this is very much a "it depends answer" but in general, would it be better to have a narrow clustered index with high usage query led design of narrow non clustered indexes?</p>
  
  <p>And following on that, is it better to have wider non-clustered indexes or rather more non clustered indexes targeting specific use cases?</p>
  
  <p>The reason why I ask this is that we have quite a wide clustered index that includes column a and column b and those same columns are in an index that is quite wide as well. When I then do a query, sql still suggests another new index with column a and column b which seems to me to be quite redundant then?</p>
  
  <p>Any help and advice would be appreciated and feel free to correct any logical gaps/misconceptions I have in my understandings :-).</p>