Question: I'm a newbie at SOAP and web services (2 day experience).

I use Bonita Open Solution as a BPMS in which I have a 'WebServer SOAP 1.2' connector. I need to get and write data from/into a database using SOAP. I don't want to use the 'SQL Server' connector which is based on JDBC because the system will be tightly-coupled.

Is there any already implemented SOAP web service in SQL Server 2008 to do that or should I develop my own? In case I should develop my own, I'm guessing the best way to do so is using ASP.NET, am I right?

Answer: 
Before you do *anything*, you need to decide exactly which data is required by the BPMS system and what access it requires. For instance, it may need read access to some data, but read and write to other data. Your service should only expose the data and operations which are actually *required*, and nothing more.

Your data is precious - don't expose more of it than necessary.

I recommend that you use Entity Framework in a database-first mode, but only add the required tables to the model. Then, simplify the model by removing columns which are not required, simplifying relationships, etc. Thus, you are exposing a conceptual model of your data which makes sense to the consumer, rather than having to expose every implementation detail of your database (do you really need to expose every junction table, for instance?)

It is then pretty simple to write a WCF service that uses Entity Framework to do the hard work of data access.
Even if deprecated, Sql Server 2008 has native SOAP web services (see [Native XML Web Services: Deprecated in SQL Server 2008](https://msdn.microsoft.com/en-us/library/cc280436%28v=sql.105%29.aspx)).

You need to balance the risk of a Sql Server upgrade against the cost of developing (and maintain) a custom service.