WordPress MU

I have seen the multi database solutions at WPMUDEV and have some questions for you having experience of that hack:

1. For which count of blogs would you recommend using that hack? 100, 1000, 5000, 10000? When is it needed?

2. Switching to multiple DB at later time, is it possible, or should it be there from the begining?

3. Is the plugin filling one DB at a time or scattering the blogs on the many DB that are used?

4. Is this solution working well with the plugins that create tables for individual blogs?

1) How many blogs is really up in the air. It can depend on so many things as many blogs would be the normal reason, but having fewer active blogs might do the same thing. I have heard people justify it with less than 100 blogs since you can also have VIP databases.

2) Their solution has an import script, but being honest the sooner you use it the easier it is as migration with a few blogs and pissing off a few users is one thing, many is another.

3) It scatters across many DB's based on the blog hash and is pretty even right away.

4) Like HyperDB, you can define what are global versus blog tables in the configuration.

Trent

Thank you Trent for this great answer!

Does it has to be 16 databases och the amount can be used during "installation". Seems like 16 DB is guite a lot if the site will not be that huge ...

I use it on a "smaller" site with 16 dbs. Makes it *much* easier to manage.

Totally worth it.

and i also recommend starting out with it as soon as you can. Moving a couple hundred blogs around is not real good for the nerves.

16 databases is usually the minimum because the system identifies the correct database to use with a (an?) Hexadecimal number.

andrea_r, what is easier to manage? I mean a database with 40 blogs or 400 blogs seems to be a pain anyway, where phpadmin can't be used, so it seems like it is the same to manage or?

But I will definitely take your advice and look at it. Thanks.

Multiple databases are a lot easier to manage and administer, than a large single database.
Even form the point of view of load times of phpmyadmin pages (though I don't use it), backing up databases.
And should the worst happen and you have a db problem, you only have to take a limited number of users offline whilst you fix it.

I can see that now. Thanks.

Ah, see... even with a smaller number of blogs, splitting them across 16 dbs makes it *way* easier to manage because then things like phpmyadmin will be able to look at them without barfing all over the place. :D

Huh. I suppose I just said what cafespain did, only differently.