Multiple Databases

[Anon]

We have about 10 dbs right now. We are considering creating a database for consolidating all our tables. I am concerned the difference in the load of having all tables in one db. The reason for this is to only have to make one db connection when joining tables in different databases. Any help is appreciated!

[toma42]

Any help is appreciated!

You didn't ask any questions.

[Anon]

Is multiple databases preferable to one database? I know as far as database normality that multiple databases is preferable, but what about performance?

[smarlowe]

Related information should generally reside within the same database instance.

[Anon]

I totally agree, but will making multiple database connections slow down the performance?

[Anon]

Well... there is more to this that just talking about one, two or ten db's. The size of each of them (and the size of them combined) should also be calculated.

Also, usage. If 3 ppl/10minute use the database or 15000/minute use it. And even security. If one table crawls under, at least the rest is okay.

This is just ideas, as im not familiar with the question. But someone else might have more information to share. I'm mysekf interested.

// Thomasson

[smarlowe]

yes, somewhat. If you are handling thousands of users at a time, having multiple connects could be an issue. If you've only got a few dozen users, then no big deal really.

The big advantage is that you can join and union related information if they're in the same instance, but if they are in different db instances, then joins may be much slower and more difficult (as in MySQL) or virtually impossible (as in postgresql) without using temp tables and transferring data around from one db to another.