Re: Suggestion?

[Mikael Ronström]

Hi,

fz wsc wrote:
> Now, to be a partition key, a column has to be
> included in PRIMARY KEY().

It's perfectly reasonable that this should not be a requirement. However
in 5.1 we don't support global indexes for partitioning and thus it would
not be scalable to ensure uniqueness constraint by checking in all partitions
for each insert done into the table. So most likely this constraint will
disappear in later MySQL versions, most likely at the same time as we
support global indexes.

Rgrds Mikael


> For instance, in the following statement, I don't
> really want `p1` be included in the PRIMARY KEY.
> Is this suggestion reasonable?
>
> CREATE TABLE `t1` (
> `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
> `p1` varchar(50) NOT NULL,
> PRIMARY KEY (`id`,`p1`)
> ) ENGINE=InnoDB DEFAULT CHARSET=utf8
> ROW_FORMAT=DYNAMIC AUTO_INCREMENT=1
> COLLATE utf8_general_ci
> PARTITION BY LINEAR KEY(`p1`)
> PARTITIONS 4;