populate a top tree view with a query data

Dear experts
how do i populate a treeview with a query

        Dim nusa10 As String = "SELECT distinct proyecto from jsmtmp1"
        Dim cmd10 As New OleDbCommand(nusa10, cn)

i want to populate with the result of that query
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Fernando SotoRetiredCommented:
The  ExecuteScalar method will, "Executes the query, and returns the first column of the first row in the result set returned by the query. Additional columns or rows are ignored." from Microsoft documentation. So there is only one value coming back from the query, not enough data to fill a TreeView.

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ErnestoAuthor Commented:
Do you have a code for explain?
Fernando SotoRetiredCommented:
Your query,
 Dim nusa10 As String = "SELECT distinct proyecto from jsmtmp1"

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when executed with this statement,

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will only return one single value which in this case you are not storing it. To capture the return value you would do something like this,
Dim returnVal = cmd10.ExecuteScalar()

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ErnestoAuthor Commented:
yes fernando, but i need the statements for the treeview node, do you have an specific example for populate the top of the tree with the query?
Fernando SotoRetiredCommented:
Hi edo60;

To assign the value returned from the query you can do the following
Dim returnVal = cmd10.ExecuteScalar()
Dim tn As New TreeNode(returnVal)

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Visual Basic.NET

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