code: static void assertTableExistence(CallInfo callInfo, DB db, String tableName, boolean expected) {
      boolean actual = tableExists(callInfo, db, tableName);
      SimpleAssertion assertion = new SimpleAssertion(null, expected, actual);
      db.log(callInfo, assertion);
      if (!assertion.passed()) {
        throw new DBAssertionError(callInfo.getMessage());
      }
    }
docs: Assert if table exists or not.
  
  @param callInfo Call info.
  @param db Database.
  @param tableName Table.
  @param expected Expect if table exists or not.