* Zardosht Kasheff <zardosht@stripped> [11/04/09 03:43]:
> In MySQL 5.1, a storage engine can allow other threads to write to a
> table while an index (via handler::add_index) is being created. To do
> so, one can set the lock_type to TL_WRITE_ALLOW_WRITE when
> handler::store_lock is called.
> In MySQL 5.5, this does not work, because a "metadata lock", or MDL
> has been added to the system. Is there any way to get this to work in
> MySQL 5.5?
I don't think it is possible to do this in MySQL 5.5.
We work on alleviating this issue in future releases.
Dmitry Lenev, Software Developer
Oracle Development SPB/MySQL, www.mysql.com
Are you MySQL certified? http://www.mysql.com/certification