title: Invalid default value for timestamp column
body: <p>I can't find why this is not valid in MySQL 5.7 (tested with 5.7.16)</p>
  
  <pre><code>CREATE TABLE TEST_TABLE (ts TIMESTAMP DEFAULT CURRENT_TIMESTAMP);
  INSERT INTO TEST_TABLE() VALUES ();
  DROP TEMPORARY TABLE IF EXISTS TMP_TEST;
  CREATE TEMPORARY TABLE TMP_TEST SELECT * FROM (SELECT ts FROM TEST_TABLE) wrap;
  </code></pre>
  
  <p>I am getting this: Error Code: 1067. Invalid default value for 'ts'</p>
  
  <p>Am I missing something or is it a mysql bug?</p>