[Mr. tech]

If I create a script that allows multiple people to sign up for accounts, is it ok if they use the same database?

http://www.campaignmonitor.com is an email mailout software that allows you to signup and create newsletters, add subscribers etc. That must mean they would have millions of records in their database from all their accounts.

Would a site like campaign monitor use just one database to store all their information or would they need multiple databases? What is the best way to approach this?

[kmote]

You would only have one database. The normal way to handle users would be to have a users table.

[CrazeD]

One database, multiple users. An SQL database can hold essentially limitless data, dictated by the hardware of the server it is being run on.

[j.smith1981]

There's basically 2 forms of Databases out there, Desktop databases (lack performance if multiple people are accessing them as their meant for a max of 20 I'd say concurrent connections), where as you go for the high end server databases, like MySQL for example, which is highly comparible to the propietry equivalent Oracle (which I believe is releasing version 11g), but they do release 10g as an XE free edition just limiting you to 1tb of table data (generally across your userspace/tablespace).

There is version of Microsoft SQL server, thats quite good the server ones can handle thousands of transactions (adding of users, changing of records) per second, their very fast, I mean MSSQL if you will can handle literally just over 32,000 concurrent connections for itself, but then you put your own box performance which could or will rather, if you dont have a rack server, limit the processing power of it.

Doesnt generally matter if you have quad core, you really to make a productional server you need multiple actual CPU's not cores to add processing power, the Xeon's beautifull for what it can do from HP, but at a cost of around for the servers that processor is bundled with ya talking in the region here in the UK of a price range from anything from £3,000-£5,000, really meant obviously for corporate transacting website, business data critical systems.

[tommyboy123x]

Yes. Not only should you use one database, you should use one table and call it something like members or users