title: Can indexing help even if your query doesn't have a WHERE Clause in T-SQL?
body: <p>I'm having a problem on optimizing the query.</p>
  
  <p>I have a table that has a 70+Million rows in it and it doesn't have an index, I want to put an index for it. I'll just ask if putting an index on it will help even if the queries executed for that specific table doesn't have a WHERE Clause?</p>
  
  <p>i.e. </p>
  
  <pre><code>CREATE CLUSTERED INDEX idx_1 on Table
  (
   Column1,
   Column2,
   Column3
  )
  </code></pre>
  
  <p>Will the query below be optimized if I selected the specific columns which the index was created and without a <code>WHERE Clause</code>?</p>
  
  <pre><code>SELECT Column1, Column2, Column3 FROM Table
  </code></pre>
  
  <p>I know that the WHERE Clause will make the an INDEX SEEK on the execution plan, but what if index was created on the table and no WHERE clause included on the query, will it run fast too?</p>