Data.Relation and reflexive relation

[Yvonne.Lebhardt]

Hello,

I need to build a treeview in a winforms application. The datasource is
a dataset. I've the following tables

products(prodGUID, name)
categorys(catGUID, name, prodGUID, parentcatGUID)

So a tree might look like this:

rootnode
|
- product 1
- category 1
- category 2
- category 3
- category 4

To build a Tree with products and categorys is no problem. But how do I
handle the reflexive relation of the categorys (done with
parentcatGUID)??

If I set a reflexive Daterelation I get an error like "same table
cannot be a child-table in two cascaded realtions" (translated from
german).

Do you have any example for me

Thanks Yvonne

 

[Ray Booysen]

Hi Yvonne

On a side note, shouldn't the products table have a foreign key to
categorys not the categorys table having the prodGUID?

Regards
Ray

 

[Sahil Malik [MVP]]

Yvonne,

Just as in a database, add one datarelation for the product->category
relation. Then add another from category->category. The top parent category
node FK must be null to enforce such a relationship. It should work then.

- Sahil Malik [MVP]
ADO.NET 2.0 book -
http://codebetter.com/blogs/sahil.malik/archive/2005/05/13/63199.aspx

 

[Sahil Malik [MVP]]

Good catch.

- Sahil Malik [MVP]
ADO.NET 2.0 book -
http://codebetter.com/blogs/sahil.malik/archive/2005/05/13/63199.aspx
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[Yvonne.Lebhardt]

Hi Ray,

no, i don't talk about product-categories in the classic way.

The relation is product-category-question. Each product has serverall
categories with many questions in each category.

Yvonne

 

[Cor Ligthert [MVP]]

Yvonne,

Do you mean that you need the childdatarows of the childdatarows in a
relation?

datarow.getchildrows
http://msdn.microsoft.com/library/d...rfsystemdatadatarowclassgetchildrowstopic.asp

I hope this helps,

Cor