title: SQL Server : For 3 columns, difference between "one index per column" / "one index for all"
body: <p>I am configuring a simple table in SQL Server. It is named "LOG" and as you might expect, it is used to record logs, for later monitoring/searching/grouping the use of various applications in various manners.</p>
  
  <p>The table is declared somewhat like that (simple syntax) :</p>
  
  <pre><code>LOG {
     user   varchar(8),
     timestamp  datetime,
     appname   varchar(16)
  }
  primary key(user,timestamp,appname)
  </code></pre>
  
  <p>Should I index each column in a separate index? All three in the same index?
  Clustered / non-clustered?</p>
  
  <p>I'd be happy to see what logic/knowledge you would apply here.</p>