title: How's the performance of MySql ROW_NUMBER() function with a large dataset?
body: <p>How's the performance of MySql ROW_NUMBER() function with a large dataset for a query like this:</p>
  <pre><code>select *, ROW_NUMBER() OVER (ORDER by ts_col, pk_col)
   where other_col = 'value'
  </code></pre>
  <p>...</p>
  <p>other_col will have a few distinct values</p>
  <p>MySQL's explain plan does not show details on it's execution. Will indexing help here?</p>