title: Actual size of BigQuery table's snapshot
body: <p>BQ <a href="https://cloud.google.com/bigquery/docs/table-snapshots-intro" rel="nofollow noreferrer">documentation</a> states that</p>
  <pre><code>Storage costs apply for table snapshots, but BigQuery only charges for data in a table snapshot that no longer exists in its base table, or that has changed in its base table
  </code></pre>
  <p>Is there any way (UI/programmatic) to check storage size of given snapshot (storage I am billed for)? When checking table's metadata I see <code>size</code> entry which only tells me the size of the base table at the moment of taking snapshot.</p>
  <p>Example:<br />
  <code>base_table</code> size: 22GB<br />
  <code>base_table_snapshot</code> size: 22GB</p>
  <p>then after addition of some data to <code>base_table</code> UI shows</p>
  <p><code>base_table</code> size: 24GB<br />
  <code>base_table_snapshot</code> size: 22GB</p>
  <p>but 22GB was already snapshotted (and did not change), so I should be billed for 24GB.</p>