or rewrite commits, the
    table will appear empty to concurrent transactions, if they are using a
    snapshot taken before the DDL command committed.  This will only be an
    issue for a transaction that did not access the table in question
    before the DDL command started — any transaction that has done so
    would hold at least an <code class="literal">ACCESS SHARE</code> table lock,
    which would block the DDL command until that transaction completes.
    So these commands will not cause any a