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Chapter 11: Developing BI Applications with ADOMD.NET 429
lvItem.SubItems.Add(String.Empty)
End If
Next iField
' Add the item to the listview
rstListView.Items.Add(lvItem)
Loop While (dr.Read())
' Close the DataReader
dr.Close()
Catch ex As Exception
MessageBox.Show(ex.Message)
End Try
End Sub
Private Function ParseColName(ByRef sColName As String) As String
Dim sShortName As String
Dim iFound As Integer = sColName.LastIndexOf("[") + 1
sShortName = sColName.Substring(iFound, sColName.Length() - _
(iFound + 1))
Return sShortName
End Function
At the top of the subroutine, you can see that an AdomdConnection object is passed
in. The next statement creates a new AdomdCommand object named cmd and uses an
MDX SELECT statement as a parameter on the constructor. This very simple MDX
SELECT statement, when executed, will set the column and row dimensions of the
multidimensional results with employee last names and English name months. The
NON EMPTY keywords are used, so that only the nonempty data will be selected.
Next, an AdomdDataReader is initialized to receive the multidimensional data, and
a ListViewItem object is initialized.
The next two lines clear the Items and Columns from the ListView control that was
placed on the Windows form at the program design phase. The AdomdCommand’s
ExecuteReader method is then called and returns the AdomdDataReader named dr. As

you can see from the code listing, the ExecuteReader is called inside the Try-Catch
loop. Any exceptions that may occur are trapped by the Try-Catch loop, and a message
will be displayed to the user.
After the data has been retrieved with the ExecuteReader method and output to the dr
AdomdDataReader object, the Read method of the dr object is called to read the first data
and set up the column names for output to the ListView control. The next few lines of
code use a For Next loop to add columns to the ListView control. In this example,
the dr object’s GetName method is used to set the column text with the names of the
430 Microsoft SQL Server 2005 Developer’s Guide
retrieved columns. Because the GetName method returns the complete name of the
column, including the dimension hierarchy, we use a simple ParseColName function to
strip the column name of unwanted characters. For example, the dr.GetName method
returns the value of ‘[Dim Time].[English Month Name].&[April]’. We want only
the month name to appear on the column heading of the ListView control, so we pass
the whole string to the ParseColName function and strip out the unwanted hierarchy
description, returning the short text value of ‘April’. The ParseColName function is
included in the code listing.
Once each of the columns has been added to the ListView control and the column
names have been added to the column text, a Do While is used to initialize a new
ListViewItem and read each element of the AdomdDataReader. Inside the Do While
loop, a For Next loop iterates through each of the dr object’s row items and adds them
to the new ListViewItem. The Do While loop then reads the next row item of the dr
object using the dr.Read method, and adds a ListViewItem to the ListView control
until all of the rows of the dr object have been read.
The dr AdomdDataReader object is then closed using the dr.Close method, and
the results are displayed to the user, as shown in Figure 11-4.
Figure 11-4 AdomdDataReader results
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Using the XMLReader Object
The AdomdCommand object also allows returned multidimensional data to be displayed

in XML format. To view data in XML format, the AdomdCommand’s ExecuteXmlReader
method is used that returns an XmlReader object. The next subroutine shows retrieving
data to an XmlReader and displaying it in a Listbox control:
Private Sub XMLReader(ByRef cn As AdomdConnection)
Dim cmd As New AdomdCommand("SELECT NON EMPTY " & _
"[Dim Time].[English Month Name].MEMBERS ON COLUMNS, " & _
"NON EMPTY {[Dim Employee].[Last Name].MEMBERS} ON ROWS " & _
"FROM [AdventureWorksDW]", cn)
Dim xmlReader As System.Xml.XmlReader
Try
' Execute the XML query
xmlReader = cmd.ExecuteXmlReader()
xmlReader.MoveToContent()
While xmlReader.Read()
Select Case xmlReader.NodeType
Case XmlNodeType.Element
rstListBox.Items.Add("<{0}>" & xmlReader.Name)
Case XmlNodeType.Text
rstListBox.Items.Add(xmlReader.Value)
Case XmlNodeType.CDATA
rstListBox.Items.Add("<![CDATA[{0}]]>" & _
xmlReader.Value)
Case XmlNodeType.ProcessingInstruction
rstListBox.Items.Add("<?{0} {1}?>" & _
xmlReader.Name & xmlReader.Value)
Case XmlNodeType.Comment
rstListBox.Items.Add("<! {0} >" & _
xmlReader.Value)
Case XmlNodeType.XmlDeclaration
rstListBox.Items.Add("<?xml version='1.0'?>")

Case XmlNodeType.Document
Case XmlNodeType.DocumentType
rstListBox.Items.Add("<!DOCTYPE {0} [{1}]" & _
xmlReader.Name & xmlReader.Value)
Case XmlNodeType.EntityReference
rstListBox.Items.Add(xmlReader.Name)
432 Microsoft SQL Server 2005 Developer’s Guide
Case XmlNodeType.EndElement
rstListBox.Items.Add("</{0}>" & xmlReader.Name)
End Select
End While
xmlReader.Close()
Catch ex As Exception
MessageBox.Show(ex.Message)
End Try
End Sub
As you can see at the top of the listing, an AdomdConnection object is passed
in to the subroutine. The next statement creates the AdomdCommand object using
the MDX SELECT statement in its constructor. The next line shows the creation
of an XmlReader object. The XmlReader is found in the System.Xml namespace;
therefore, this line of code shows the creation of the XmlReader using the fully
qualified namespace hierarchy.
The AdomdCommand’s ExecuteXmlReader is then executed and returns the
xmlReader object. The Try-Catch loop is employed here to catch any exceptions that
may occur and displays the exception message to the user. The next statement calls
the xmlReader’s MoveToContent method that skips over random XML markup. The
xmlReader’s Read method is called in a While loop to read through each retrieved
row in the xmlReader. Inside the While loop a Select Case statement is used to
format the information and add it to the Listbox control found on the Windows form.
When all of the rows have been read from the xmlReader, it is closed and the

resulting Listbox is displayed to the user.
Using the CellSet Object
The ExecuteCellSet method of the AdomdCommand object is called to return
multidimensional results to a CellSet. A CellSet is similar to a DataSet; however,
a DataSet can contain only two-dimensional relational data, but a CellSet can
contain multidimensional data. A CellSet’s contents consist of a collection of cells
that are organized along multiple dimensions. The code listing that follows shows
creating a CellSet with an AdomdCommand’s ExecuteCellSet method and displays
the retrieved information in a Listbox:
Private Sub CellSet(ByRef cn As AdomdConnection)
Dim cmd As New AdomdCommand("SELECT NON EMPTY " & _
"[Dim Time].[English Month Name].MEMBERS ON COLUMNS, " & _
"NON EMPTY {[Dim Employee].[Last Name].MEMBERS} ON ROWS " & _
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"FROM [AdventureWorksDW]", cn)
Dim cs As CellSet
' Clear the ListBox
rstListBox.Items.Clear()
Try
' Execute the query and return a cellset
cs = cmd.ExecuteCellSet()
rstListBox.Items.Add("The cellset has " & cs.Cells.Count & _
" cells organized along " & cs.Axes.Count & " axes")
Dim axCol As Axis = cs.Axes(0)
Dim axRow As Axis = cs.Axes(1)
Dim posRow As Position, posCol As Position
For Each posRow In axRow.Positions
Dim sCell As String = 0
For Each posCol In axCol.Positions
sCell += cs(posCol.Ordinal, _

posRow.Ordinal).FormattedValue() & vbTab
Next
' Add the item to the listbox
rstListBox.Items.Add(sCell)
Next
Catch ex As Exception
MessageBox.Show(ex.Message)
End Try
End Sub
Again, an AdomdConnection object is passed in at the top of the subroutine and an
AdomdCommand object is created using the SELECT MDX statement. A CellSet
object is then created, and the Windows form Listbox control is cleared of any
leftover information.
The next statement shows calling the AdomdCommand’s ExecuteCellSet method and
returning the results to the CellSet. The CellSet now contains a collection of query axes,
which help to organize the information within the CellSet, and a collection of cells. In
this example, there are two axes in the CellSet Axes collection, one for the columns in
the CellSet and one for the rows in the CellSet. The next statements initialize variables
for the Axes collections and Position variables to select and output the coordinates of the
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cells in the CellSet. Nested For Next loops are set up next, to iterate through the axes and
add the cells to the Listbox according to the position coordinates of the cells.
The final results are displayed to the user as shown in Figure 11-5.
Using the AdomdDataAdapter Object
The AdomdDataAdapter is used in combination with the AdomdConnection object
and the AdomdCommand object to fill a CellSet with multidimensional data and
then resolve the information back to a SQL Server database.
The following example illustrates how to use an AdomdConnection, create an
AdomdCommand object, and populate a new DataTable with the AdomdDataAdapter.
The contents of the DataTable will then be displayed to the user in a grid:

Private Sub AdomdDataAdapter(ByRef cn As AdomdConnection)
Dim cmd As New AdomdCommand("SELECT NON EMPTY " & _
"[Dim Time].[English Month Name].MEMBERS ON COLUMNS, " & _
"NON EMPTY {[Dim Employee].[Last Name].MEMBERS} ON ROWS " & _
"FROM [AdventureWorksDW]", cn)
Dim da As New AdomdDataAdapter(cmd)
Dim dt As New DataTable
Figure 11-5 CellSet results
Chapter 11: Developing BI Applications with ADOMD.NET 435
Try
da.Fill(dt)
rstDataGridView.DataSource = dt
Catch ex As Exception
MessageBox.Show(ex.Message)
End Try
En
d Sub
An instance of the AdomdConnection object is passed in at the top of the subroutine.
The next statement creates an AdomdCommand object and sets its CommandText
property to the SELECT MDX statement and Connection property to the previously
passed-in AdomdConnection object. Next, an instance of a AdomdDataAdapter is
created and its SelectCommand property is set to the AdomdCommand object. An empty
DataTable is then created, which will be populated with the results of the SELECT query
command. The DataTable is then filled using the AdomdDataAdapter’s Fill method,
which is executed inside a Try-Catch block. If the Fill method fails, the code in the
Catch block is executed and a message box appears showing the error message. Finally,
a DataGrid’s DataSource property is set to the DataTable and displayed to the user as
shown in Figure 11-6.
Figure 11-6 AdomdDataAdapter results
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Using the CubeDef Object
Using the CubeDef object in ADOMD.NET, you can retrieve metadata information
about a cube, including its dimensions, measures, and named sets. The CubeDef object
contains only metadata information and no actual cell data. The AdomdConnection
object contains a collection of cubes that are in the database specified for the
AdomdConnection object.
The following code listing shows how to display some metadata information from
a cube in a Listbox control:
Private Sub CubeDef(ByRef cn As AdomdConnection)
Dim cubDef As CubeDef = cn.Cubes(0)
' Clear the Listbox
rstListBox.Items.Clear()
rstListBox.Items.Add(" ** Measures ** ")
For Each meas As Measure In cubDef.Measures
rstListBox.Items.Add("Name : " & meas.Name)
rstListBox.Items.Add("Description : " & meas.Description)
rstListBox.Items.Add("Expression : " & meas.Expression)
rstListBox.Items.Add("Units : " & meas.Units)
Next
rstListBox.Items.Add(" ** Dimensions ** ")
For Each dimen As Dimension In cubDef.Dimensions
rstListBox.Items.Add("Name : " & dimen.Name)
rstListBox.Items.Add("Description : " & dimen.Description)
rstListBox.Items.Add("Hierarchy : " & _
dimen.Hierarchies(0).ToString())
Next
End Sub
The AdomdConnection object is passed in at the top of the subroutine, and
a CubeDef object is created and set with the information from the first cube in
the AdomdConnection’s Cubes collection. The CubeDef contains collections for

Dimensions, Measures, NamedSets, and KPIs that are associated with each specified
cube in the database.
The next statements in the code listing clear the Listbox of any previous items,
and then two For Next loops are set up to iterate through the Measures collection
of the CubeDef and the Dimensions collection of the CubeDef, adding each of the
collection elements to the Listbox for display to the user.
Chapter 11: Developing BI Applications with ADOMD.NET 437
Summary
ADOMD.NET is a database provider that allows you to develop database applications
that communicate with multidimensional data sources. In this chapter you learned
about some of the SQL Server Analysis Services capabilities as well as how to develop
BI applications that access some of those capabilities. SSAS allows you to analyze
your data to determine trends and patterns to meet your business goals. Developing
visual applications with ADOMD.NET to show those trend and patterns can increase
the usability of that information.
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