Association will take effect on snow flake schema join?

Dose associations take effect for the snow flake join, for example, fact join dim_A,Dim_B, are star schema join, and join Dim_c, Dim_C join is not on fact column, it is on DIm_A and Dim_B column, how to make the association take effect?
user
08-09-2019 04:52:34 -0400

6 Answers

Hi, In Denodo terminology, the concept of association comes into the picture to specify the relationship between two views. Once the base view is created from the Snowflake data source, its structure is similar to any other view created by connecting to any other data source. It is independent of any particular type of operations performed using these views, since structurally all the views correspond to their own VQLs. You may want to refer to [Associations in Denodo]( https://community.denodo.com/kb/view/document/Associations%20in%20Denodo?category=Combining+Data) to get more details. Hope this helps!
Denodo Team
09-09-2019 08:49:17 -0400
not very understand your point. for example below, do you have some idea to implement the association: select A.m, A.n, B.o, B.p, C.q, D.r, E.s, E.t from Fact A join dim_1 B on A.b = B.b join dim_2 C on A.c = C.c join dim_3 D on A.d = D.d join dim_4 E on B.x = E.x and C.y = E.y and D.z = E.z For A->B, A->C, A-D, it is easy to have association. How about A--> E, how to implement the association?
user
09-09-2019 10:08:24 -0400
also, "Once the base view is created from the Snowflake data source", what does "base view" here you mean?
user
09-09-2019 10:10:34 -0400
Hi, Base views are the views that you create from underlying data source that you create in Denodo Platform. I am assuming that this syntax is from underlying Snowflake tables and not related to Denodo, and you are trying to: • Connect to snowflake by creating a Data Source in Denodo • Create base views on using this Data Source • Implement an association in Denodo between two views (created from underlying tables A and E) which do not have any field in common, but have another view (created from underlying table B) which has some commonality with both of them If this understanding is correct, then you cannot have an association created between A and E directly. However, you should be able to traverse from A to B and then B to E using associations, in the RESTful web services. I would recommend referring to [How to connect to Snowflake from Denodo](https://community.denodo.com/kb/view/document/How%20to%20connect%20to%20Snowflake%20from%20Denodo?category=Data+Sources) and [Associations in Denodo]( https://community.denodo.com/kb/view/document/Associations%20in%20Denodo?category=Combining+Data) to get a detailed understanding. Hope this helps!
Denodo Team
18-09-2019 05:57:30 -0400
snowflake is not kind of source, it is a kind of model, every DW database may contain this kind of table model and relationships. one more thing, doese denodo association relationship just for two columns, can we define these relationship in association: A join B on A.a between B.c and B.d ? "However, you should be able to traverse from A to B and then B to E using associations, in the RESTful web services." Why mentioned "RESTful web services" here? I just use the common function, not provide and web service, any relationship with "RESTful web services"?
user
20-09-2019 03:21:41 -0400
Hi, In Denodo’s terminology, Data Source is the source from where Denodo fetches the data once the view is executed. To Denodo, it does not matter what the underlying structure is (which is model in case of Snowflake). Association is a definition between two views to specify the relationship that connects them. At a logical level, let’s say, View A is related to employee information. View B is related to sales information (i.e. sales performed by each employee). Employee id might be the common field which is present in both views, which essentially helps visualize the two tables as related to each other in some way. Hence, association in Denodo helps you understand the relationship between two views in a Data Modelling context. This concept is not to be confused with JOINS in Denodo, where you are joining two views based on a condition to create a new view which can pull out all information from two underlying view when queried. I would highly recommend referring to [JOINS](https://community.denodo.com/docs/html/browse/7.0/vdp/vql/queries_select_statement/from_clause/join_operation) and [ASSOCIATIONS](https://community.denodo.com/kb/view/document/Associations%20in%20Denodo?category=Combining+Data) to understand that these are two different concepts. Coming to your second question, RESTful Web Service is a default catalog provided by Denodo to views present in Denodo server. In case of views associated with each other, you can navigate from one view to another using this catalog. You can refer to [RESTful Web Services](https://community.denodo.com/tutorials/browse/basics/4connect3consume) for more details. Hope this helps.
Denodo Team
30-09-2019 06:41:20 -0400
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