title: Proper way of creating indexes for same column when "include" columns are different
body: <p>Let's say I have 2 stored procedures and 1 table.</p>
  
  <ul>
  <li>Table name: <code>Table_A</code></li>
  <li>Procedure names: <code>proc1</code> and <code>proc2</code></li>
  </ul>
  
  <p>When I run the <code>proc1</code> with execution plan, it suggests me to create an index for <code>Table_A</code> for <code>tblID</code> (which is NOT a Primary Key) column and suggests to include <code>column_A</code> and <code>column_B</code>.</p>
  
  <p>And the <code>proc2</code> suggests to create an index for <code>Table_A</code> again, for <code>tblID</code> column but this time it suggests to include <code>column_B</code> and <code>column_C</code> (it suggests <code>column_C</code> instead of <code>column_A</code> for this procedure)</p>
  
  <p>So my question is, if I have create an index which included all suggested columns like: </p>
  
  <pre><code>CREATE NONCLUSTERED INDEX indexTest
  ON [dbo].[Table_A] ([tblID])
  INCLUDE ([column_A],[column_B],[column_C])
  </code></pre>
  
  <p>Does that cause any performance issue? </p>
  
  <p>Is there any disadvantage of gathering <code>INCLUDE</code> columns? </p>
  
  <p>Or should I create 2 different indexes as:</p>
  
  <pre><code>CREATE NONCLUSTERED INDEX indexTest_1
  ON [dbo].[Table_A] ([tblID])
  INCLUDE ([column_A],[column_B])
  
  CREATE NONCLUSTERED INDEX indexTest_2
  ON [dbo].[Table_A] ([tblID])
  INCLUDE ([column_B],[column_C])
  </code></pre>
  
  <p><strong>UPDATE:</strong> I would like to add one more thing to this question.</p>
  
  <p>If I do the same thing for primary fields as well: </p>
  
  <p>I mean, </p>
  
  <p>proc-1 suggested to create an index on <code>tblID</code> field. And proc-2 suggested to create an index on <code>tblID</code> and <code>column_A</code>. </p>
  
  <p>If I gather them as : </p>
  
  <pre><code> CREATE NONCLUSTERED INDEX indexTest_3
      ON [dbo].[Table_A] ([tblID],[column_A])
      INCLUDE ([[column_B])
  </code></pre>
  
  <p>Does that cause a performance issue? Or Should I create 2 separate index for suggested primary fields?</p>