坑一：Incorrect table definition; there can be only one TIMESTAMP column with CURRENT_TIMESTAMP in DEFAULT or ON UPDATE clause
解：在MySQL5.5发现这个问题，一个表里只能有一个TIMESTAMP的字段使用当前时间作为默认值或者作为更新值。在5.6开始接触了这个限制，官方原文如下：
Previously, at most one
TIMESTAMPcolumn per table could be automatically initialized or updated to the current date and time. This restriction has been lifted. AnyTIMESTAMPcolumn definition can have any combination ofDEFAULT CURRENT_TIMESTAMPandON UPDATE CURRENT_TIMESTAMPclauses. In addition, these clauses now can be used withDATETIMEcolumn definitions. For more information, seeAutomatic Initialization and Updating for TIMESTAMP and DATETIME.
坑二：在升级MySQL到5.7时，如果表定义中TIMESTAMP的默认值为0,那么也会报错
解：5.7的默认SQL Mode 中NO_ZERO_DATE,NO_ZERO_IN_DATE对此产生了影响，一个是禁止0，另一个禁止全0的date,形如’0000-00-00‘而我们需要做的就是在my.cnf中去除这2个mode或者新增一行不含这2个mode的sql_mode行，然后重启服务即可。
参考
http://dev.mysql.com/doc/relnotes/mysql/5.6/en/news-5-6-5.html
http://dev.mysql.com/doc/refman/5.6/en/sql-mode.html#sql-mode-setting