http://ayende.comAyende @ RahienCopyright (C) Ayende Rahien 2004 - 2021 (c) 202660on: Left.Id.ToString().Equals(Right.UserId) && Left.UserName == Right.Name http://ayende.com/2654/rhino-etl-thinking-about-joins-merges#comment4http://ayende.com/2654/rhino-etl-thinking-about-joins-merges#comment4Fri, 27 Jul 2007 11:19:56 GMTHmm good start I think. What about a multi-key (I'm not sure about the English term) join? http://ayende.com/2654/rhino-etl-thinking-about-joins-merges#comment3http://ayende.com/2654/rhino-etl-thinking-about-joins-merges#comment3Fri, 27 Jul 2007 11:16:04 GMTDerick, I am not limited to the alternative I have brought up, I am certainly opened to new stuff http://ayende.com/2654/rhino-etl-thinking-about-joins-merges#comment2http://ayende.com/2654/rhino-etl-thinking-about-joins-merges#comment2Thu, 26 Jul 2007 21:21:28 GMTi'm not sure i like either of those syntax options, actually. Neither of them allows for joins across multiple tables where the join happens down the chain of tables. for example, how would I join TableA.Field1 to TableB.Field2 to TableC.Field3? if you modify the joinTransform line like this, you can accomplish what I am saying with multiple joinTransforms, though: joinTransform Source to UsersAndOrganizations: I also think it would be hard to have complex joins, like Or clauses, with those two syntax specs. you would need something closer to real SQL, while still mainaining an object model so the final syntax would look something for multiple join chain example: joinTransform Source to UsersAndOrganizations: Left.Row.Id = Right.Row.UserId Left.Row.UserName = Right.Row.FullName transform: Row.Copy(Left) Row.OrgId = Right["Organization Id"] joinTransform UsersAndOrganizations to Departments Left.Row.UserId = Right.Row.ManagerId and syntax for complex join example: joinTransform Source to UsersAndOrganizations: Left.Row.Id = Right.Row.UserId ( Left.Row.UserName = Right.Row.FullName || Right.Row.FullName = null) transform: Row.Copy(Left) Row.OrgId = Right["Organization Id"] I left the ".Row." in the Left and Right syntax so that you can add something like Left.Row.NonMatching or other specialized syntax options, as needed. http://ayende.com/2654/rhino-etl-thinking-about-joins-merges#comment1http://ayende.com/2654/rhino-etl-thinking-about-joins-merges#comment1Thu, 26 Jul 2007 20:44:41 GMT