title: Would it help to add index to BIGINT column in MySQL?
body: <p>I have a table that will have millions of entries, and a column that has <code>BIGINT(20)</code> values that are unique to each row.  They are not the primary key, but during certain operations, there are thousands of <code>SELECT</code>s using this column in the <code>WHERE</code> clause.  </p>
  
  <p><strong>Q: Would adding an index to this column help</strong> when the amount of entries grows to the millions?  I know it would for a text value, but I'm unfamiliar with what an index would do for <code>INT</code> or <code>BIGINT</code>.  </p>
  
  <p>A sample <code>SELECT</code> that would happen thousands of times is similar to this:</p>
  
  <pre><code>`SELECT * FROM table1 WHERE my_big_number=19287319283784
  </code></pre>