title: Is copying sheet data localy better for memory consumption than link cells to external file
body: <p>I'm currently working on an excel sheet that is filled by operator on a machine.</p>
  <p>Since the files are open from a server, there is some RAM efficency issues with the Excel calculation, and since i'm a student engineer, and not a computer program guy, i dont know how to mesure the impact of different types of coding.</p>
  <p>I was wondering if copying my reference sheet every file opening with something like (note that this is not real code it's for explaining the logic behind it):</p>
  <pre><code>Sub workbook_open()
  If ThisWorkbook.(&quot;Reference sheet&quot;) &lt;&gt; \\Referencefile.xlsx(&quot;Reference Sheet&quot;)
  Copy-paste on ThisWorbook.xlsx the data from Referencefile.xlsx
  End Sub
  </code></pre>
  <p>Was more Ram efficient than having for exemple this :</p>
  <pre><code>='\\Reference\[Referencefile.xlsx]Reference Sheet'!A98
  </code></pre>
  <p>In my cells.
  (Note that the &quot;referencefiles.xlsx&quot; is a 30k lines monster that takes quite some seconds to open already.)</p>
  <p>Having the &quot;Reference sheet&quot; data copied localy(same file instead of external file) would make my calculation &quot;local&quot; too, which i suppose would make my code lighter server RAM wise.
  But on the other hand, having to compare huge data sheets every opening seems heavy Ram wise too.</p>
  <p>If there no &quot;Exact&quot; answer, is there a way to calculate memory consumption of a code with code line?</p>
  <p>Thx,</p>