On Wed, Mar 23, 2011 at 2:49 PM, Andrew Hutchings <[email protected]> wrote: [...] > No, in almost every app I have ever worked on the app is passing something > like: > > SELECT * FROM t1 WHERE pkey = $somevalue;
In essence you shard on primary key, and its the application developer's responsibility to choose an appropriate primary key. If you don't query based on that key the advantages of sharding is lost as you will have to query each node. IMO, any kind of partitioning is advantageous only if you stick to a particular query model. > The flaw comes with inserts relying on auto_increment, but I don't know of > many scaling apps that use auto_increment. Would also be interested if > someone came up with a workaround for this (I'm guessing a proxy?) To auto_increment you would have to know the last value which could be residing on any shard. IMO, neither pinging all the shards won't do any good, nor storing the state at a central point. Would it not be just better to discourage auto_increment practice in a sharded environment? -- Anurag Priyam http://about.me/yeban/ _______________________________________________ Mailing list: https://launchpad.net/~drizzle-discuss Post to : [email protected] Unsubscribe : https://launchpad.net/~drizzle-discuss More help : https://help.launchpad.net/ListHelp
