You can't entirely escape this problem. Even when companies want to fit everything in a single database, they often find they can't. With enough data you'll eve

You can't entirely escape this problem. Even when companies want to fit everything in a single database, they often find they can't. With enough data you'll eventually run into scalability limitations. A quick fix might be to split different customers onto different databases, which doesn't require too many changes to the app. But now you're stuck building tools to pull from different databases to generate reports, even though you have a monolithic code base.