title: Does BigQuery Has an api to return a Checksum for a exported table
body: <p>I'm looking out if there exist a way we can get the checksum of the file (or table) that can be export from google bigquery.</p>
  
  <p>Example assuming that I exported(or downloaded) a file called 
  <code>daily-record-2018-07-10</code> from bigquery, is there a way bigquery can provide us with some <code>checksum</code> (like <code>sha1</code>, <code>md5</code> etc) so that we can precompute those checksum on our end before we start processing those files</p>
  
  <p>The reason to do so is to be sure that we aren't losing any information when are downloading(or exporting) the table. We do lose some information over the network then we can precompute the checksum and attempt again to export the table.</p>