ADO Relate 2 tables by more then one field

Introduction

The way to stablish a System.Data.DataRelation betwin 2 System.Data.DataTable's by 2 or more System.Data.datacolumn's.

In this example u must asume the existence of 2 DataTables in the DS_Geral DataSet with the acording fields ...

Sub Ex()
Dim DR_Afectacao_Producao as System.Data.DataRelation

Dim Parent (1) as System.Data.datacolumn
Dim Child (1) as System.Data.datacolumn
'This arrays of datacolumns must be delimited by the number of fields <BR>'conected in the relation, 
'thei are <FONT color=#008000>0-based</FONT>

       Parent (0) = DT_Afectacao.Columns("id_prod") 'The parent Table 
       Parent (1) = DT_Afectacao.Columns("id_xnuc") 'The parent Table
       Child (0) = DT_Producao.Columns("id_prod") 'The child Table
       Child (1) = DT_Producao.Columns("id_xnuc") 'The child Table


DR_Afectacao_Producao =  new Datarelation ("Afect_Producao", Parent, Child, _<BR>                                             false )
DS_Geral.Relations.Add(DR_Afectacao_Producao)
End Sub

Dim ChildRows_1(), foundRow As DataRow

foundRow = DT_Afectacao.Rows.Find(Sender.Selecteditem.value)
ChildRows_1 = foundRow.GetChildRows("Afect_Producao")

Example 2 Geting the Parent row:

Dim founded_ParentRow , foundRow As DataRow

foundRow = DT_Producao.Rows.Find(Sender.Selecteditem.value)
founded_ParentRow = foundRow.GetParentRow("Afect_Producao")

Summary:

The  "Rows.Find"  only finds key-values ... in the key-column of the DataTable

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