Can I have one installation spread over multiple databases?

Probably not. If you’re running such a big site get some better hosting.

This doesn’t help me, Fonglh, thanks for your answer though.

I know that it is possible to “shard”. Which apparently means running an installation over several databases on different servers. But does sharding mean that each database has the same data, or can they each house a different table?

If it is possible to have each database hold a different table, (or tables,) then it seems to me that each database would hold less data than the sum of all of them? Right?

And finally, would it be possible to have all of those databases on the same server? (The tech guy at the hosting company seemed to think that it was possible, I just needed to find out here.)

If the site was to take off in the way that I imagine, I would have to spread the load over several servers soon, anyway. For this reason, it would be a good idea for me to get a head start now rather than later.

Sonny

By default, WordPress is aware of one database. That’s why there’s only 1 set of database credentials in your wp-config.php file.

You can put different tables in different databases on the same server, but how are you going to make WordPress aware of where each table is?

It’s possible to do sharding, clustering etc etc. But all those measures require you to have total control over the database software and its configuration. That seems unlikely unless you change your hosting plan.

Load balancing and database configuration aren’t suitable questions for these forums. Try asking at server or database administration forums instead.

By default, WordPress is aware of one database. That’s why there’s only 1 set of database credentials in your wp-config.php file.

I understand this, thank you.

You can put different tables in different databases on the same server, but how are you going to make WordPress aware of where each table is?

That is the question that needs to be answered. If I knew the answer, then I wouldn’t need to ask you! I’m not ungrateful, thank you for sharing some of your time with me.

“Sharding” and “clustering” are two totally new terms to add to my vocabulary – when I finally understand what they mean. I have come across them in the search for a solution to my problem. I feel that my situation is not so unique that nobody else has thought of a way to use more than one database to run WordPress.

S

Generally HyperDB is used but that requires copies of the databases and one acting as a master.

Sometimes you just need to tell the client that their technical specifications are not doable and that they need to shell out some bucks for infrastructure. Sorry, nature of the business.

Thank you for your reply, Andrew.

When you say copies, you mean complete copies? (Not different tables in different databases?)

S

From your link I can see that it IS possible to do what I’m asking. Thank you for your input. Andrew.

S