Question

As part of an integration task I am doing, I have a column in my database that has the type nvarchar(30) and I need call a WCF service and pass through the values in this column (among others) that will then be stored in a column that has the type varchar(30) in the other database.

What should I do (presumably in the code that calls the WCF service) to convert my strings into “varchar friendly” strings?

Update: Nothing has gone wrong yet. However I will be doing an initial migration of 120,000 records through this service and then about 300 new records will be pushed through this service each day. As such, manual intervention of any kind is very undesirable and I’m just thinking about what might go wrong in advance. I have no control over the target database (with VARCHAR column), however I do know that it is SQL Server and C# for the application (not sure if they’re using ADO.NET).

Answer 1

There is nothing you have to do : all strings in .NET are UTF-16 encoded :

• when you retrieve your NVARCHAR column (using ADO .NET I presume), you automatically get a .NET string (UTF-16, any necessary conversion is automatic).
• when you store this .NET string in a VARCHAR column, any necessary conversion from UTF-16 is automatically performed as well.

See here for more information on data type mappings for Sql Server in ADO .NET.

You just have to make sure that all your strings can be converted flawlessly from the source character set to the destination character set.