Question

Does it make sense to use SQL Server Compact for a desktop application?

• How much data can it handle?
• Is it possible to use it with multiple users? What are the constraints?
• What happens when database files are broken? Is it possible to programmatically recover or would it be easy to solve the problem remotely?

Answer 1

I certainly would (and do). SQL Compact (SQLCE) has a distinct advantage in some scenarios. Now it’s in no way meant to be a replacement for SQL Server. It doesn’t scale, it isn’t made to run thousands of concurrent connections, it’s not designed for reporting services, etc, etc.

But it has a tiny footprint. Installing is a matter of just copying over DLLs. Backing it up is a simple file copy. And it can be wicked fast for storage and retrieval if you’re using table direct or BCP. Oh, and it’s free. If you just need a local data store for an app, SQL Server is a pain to deploy and configure. SQLCE is simple. Plus it can play in the same sandbox as a full SQL Server as a replication subscriber (which most other small DBs can’t).

Edit: Forgot to answer your specific questions:

• How much data can it handle? In terms of what? DB size? Throughput? Table size? Row size? My experience is that I’ve run the DB out to a a few hundred MB with no issue. I think it can hold 4GB (as of 4.0). Throughput is directly related to how you’re putting data in or taking it out. We’re using it in a solution where we’re capturing 1k rows a second with no problem. You can have 1024 columns and a max row size of 8k.
• Multiple users? Well it can handle multiple simulataneous connections (as of 3.5), so yes, that should work. I’ve used multiple connections from one user, never from multiple.
• Broken databases? Define ‘broken’. The engine has a ‘compact and repair’ method. It’s a file like any other – how do you fix a broken executable? I’ve not seen any corruptions in the field, if that’s what you’re asking (well we did on one CE device that had a bad storage card, but that’s not the engine’s fault).