LINQPad, using multiple datacontexts

c# linq linq-to-sql datacontext linqpad
Scott picture Scott · Sep 30, 2009 · Viewed 20.2k times · Source

I am often comparing data in tables in different databases. These databases do not have the same schema. In TSQL, I can reference them with the DB>user>table structure (DB1.dbo.Stores, DB2.dbo.OtherPlaces) to pull the data for comparison. I like the idea of LINQPad quite a bit, but I just can't seem to easily pull data from two different data contexts within the same set of statements.

I've seen people suggest simply changing the connection string to pull the data from the other source into the current schema but, as I mentioned, this will not do. Did I just skip a page in the FAQ? This seems a fairly routine procedure to be unavailable to me.

In the "easy" world, I'd love to be able to simply reference the typed datacontext that LINQPad creates. Then I could simply:

DB1DataContext db1 = new DB1DataContext();

DB2DataContext db2 = new DB2DataContext();

And work from there.

Answer

Joe Albahari picture Joe Albahari · Feb 8, 2011

Update: it's now possible to do cross-database SQL Server queries in LINQPad (from LINQPad v4.31, with a LINQPad Premium license). To use this feature, hold down the Control key while dragging databases from the Schema Explorer to the query window.

It's also possible to query linked servers (that you've linked by calling sp_add_linkedserver). To do this:

  1. Add a new LINQ to SQL connection.
  2. Choose Specify New or Existing Database and choose the primary database you want to query.
  3. Click the Include Additional Databases checkbox and pick the linked server(s) from the list.

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