Question

I am trying to use SQL Server Compact Edition 3.5 as a database backend for a sales application. There would be 3-4 installations of a Windows Forms application which would all (via LINQ2SQL) read from and write to one .sdf file located on a network share.

My (pretty inextensive) testing has shown that this could be viable. Documentation states that SQL Server CE supports up to 256 connections. Does SQL Server CE even lock its rows? Are there other concurrency issues that I should worry about?

Bottom line is, has anyone used SQL Server CE successfully with multiple applications connecting to same database?

Should I spare myself future headaches and go with SQL Server Express?

Answer 1

MS recommends (from Darian Miller’s comparison guide):

When you require data service
functionality, such as the ability to
support multiple, remote users, you
should start with SQL Server Express
Edition and work up the data service
family tree.

the runtime supports concurrency on the same machine, not sure about multiple machines accessing the file. in the case the file is stored over a network share, that may not fit the optimal performance profile for ce. i would say go with EE, it’s a snap to install with a simple msi.

SSCE Concurrency:

SSCE allows multiple connections to
the same database (.sdf file) from the
same application or even multiple
applications on the same computer.
This gives you more freedom to
structure your application as needed,
such as allowing the user to continue
to interact with data while performing
synchronization with a back-end
database, or to have multiple
applications on the same machine share
an SSCE data store. Transactional
concurrency locks are made by the
database engine to prevent concurrent
connections from accessing the same
records at the same time. The
technical limit on concurrent
connections for a single database is
256, but 70-80 is a better practical
limit from a performance perspective.

http://technet.microsoft.com/en-us/library/bb380177%28SQL.90%29.aspx