>* Gaston Escobar
>
>
>>I need to sincronice two mysql databases that are in different
>>places. It is imposible to centralice everything in one database.
>>Then I would need to sincronice the changes made in both of them
>>one time per day. Is there any way to do this?
>>
>>
* Roger Baklund
>This very much depends on your application. Normally some changes needs to
>be done in the table definitions.
>
>
Right, ids and foreign keys are an issue here.
>One way to get around this, is to include a new column in the table, called
>'server' in this example. [...]
>
I thought about this but I couldn't figure out how to manage foreign
keys in an elegant way.
AFAIK it's much more handy to have one single column primary key.
>A different approach could be to make sure server A only use id codes >
>100000, and server B only use id codes < 100000 or similar. This would
>require you to make a guess on how many rows will be inserted on each
>server, and could introduce a problem in the future, when this limit is
>reached.
>
>
Right, too.
So, with an nonpermanent connection the design of such an application sucks.
On the other hand one could use intervals for key assignment.
Every time a server runs out of keys it throws a warning at the admin
and rejects further inserts until it gets a new key interval.
It's a way to go at least with a low number of servers.
