Question: I caused a stupid accident in a single-disk ZFS pool, seemingly in the same way as the person in [this mailing list thread](http://www.mail-archive.com/zfs-discuss@opensolaris.org/msg25678.html), i. e., I seem to have overwritten important metadata. Can this be restored from the actual payload, or is there a way to retrieve the payload without the metadata?

Here's what I did, exactly:

* had a ZFS pool running with a single disk on one machine
* wanted to migrate it to a new ZFS pool on another machine
* forgot to `zpool export` it on the first machine
* when `zpool create` complained that the device was in use, I thought "No problem, I just took down the host, it's not in use anymore" and did `zpool create -f`

What I should have done (as I realised after RTFM) is `import` instead of `create` on the new host. Now I have a working zfspool, but the filesystems are gone / invisible.

I tried to reimport the device on the old host, and later tried `import -D`, but, quite obviously, both didn't work.

Answer: 
Check out [SQL Server Editions](http://www.microsoft.com/sqlserver/2008/en/us/editions.aspx) page at Microsoft. Also this [Feature Comparison Chart](http://www.microsoft.com/sqlserver/2008/en/us/editions-compare.aspx) at Microsoft.

Essentially:

* 1 CPU
* 4Gb maximum database size
* Unlimited users
* No SQL Server Agent support
* Still has support for procedures, triggers & functions
* Need Management Studio Express or Higher to manage the instance
Is the 4 GB limit (which in R2's case has been increased to 10 GB), implies to total storage or per database?