Description:
When upgrading from MySQL 5.5 to MySQL 5.6 the incompatible change in timestamps can break replication.
1. It is documented on http://dev.mysql.com/doc/refman/5.6/en/upgrading-from-previous-series.html
"Incompatible change: For TIME, DATETIME, and TIMESTAMP columns, the storage required for tables created before MySQL 5.6.4 differs from storage required for tables created in 5.6.4 and later. This is due to a change in 5.6.4 that permits these temporal types to have a fractional part. After upgrading from MySQL 5.5 to MySQL 5.6.4 or later, it is recommended that you also upgrade from MySQL 5.5 to MySQL 5.6 TIME, DATETIME, and TIMESTAMP types. ALTER TABLE currently allows the creation of tables containing temporal columns in both MySQL 5.5 and MySQL 5.6.4 (or later) binary format but this makes it more difficult to recreate tables in cases where .frm files are not available. Additionally, as of MySQL 5.6.4, the aforementioned temporal types are more space efficient. For more information about changes to temporal types in MySQL 5.6.4, see Storage Requirements for Date and Time Types."
This seems to indicate that it is recommended to upgrade, but not required.
2. It is not documented here:
https://dev.mysql.com/doc/refman/5.6/en/replication-compatibility.html
3. The mysql_upgade tool doesn't handle it.
It should give a warning about the possible incompatibility or upgrade to the new format.
4. As mentioned in the blog post from Ike Walker the upgrade procedure is not fully documented.
Related Bugs:
- Bug #70124
- Bug #71111
Related blog posts:
- http://mechanics.flite.com/blog/2014/05/01/upgrading-temporal-columns-from-mysql-5-dot-5-t...
How to repeat:
Read the docs, try mysql_upgrade, etc.
Suggested fix:
1. Get mysql_upgrade to upgrade the temporal columns. (or at least warn)
2. Check the documentation.
