Have you used pt-online-schema-change.html from
What do you think about this tool?
2013/7/8 Rafał Radecki <radecki.rafal@stripped>
> Hi All.
> I would like to change the layout of my production database, I would like
> to add a column to an existing table. As I think before the ALTER TABLE
> statement all access to the database should be denied/ended, then the ALTER
> TABLE should be performed, and then user/applications should be able to use
> the database once again.
> My tables is quite small ~4MB data & indexes.
> So is the ALTER TABLE on a running/opened to clients database/table
> desirable or should it be run when all access to the database/table is
> Best regards,
> Rafal Radecki.