Example in Visual Basic

Private Sub Command1_Click()
    Dim lif As MapXLib.LayerInfo
    Dim lyr As Layer
    Dim ds As Dataset
    Dim nRows As Integer
    Dim nFeatures As Integer
    Dim I As Integer
    Dim rv As RowValues
    Dim ftr As Feature
    Dim ftrs As Features
    
    ' Create a new layer from a remote database
    Set lif = CreateObject("MapX.LayerInfo.4")
    lif.AddParameter "name", "States"
    lif.Type = miLayerInfoTypeServer
    lif.AddParameter "Query", "Select * from MAPX.USA"

    lif.AddParameter "ToolKit", "ORAINET"
    lif.AddParameter "ConnectString", "SRVR=cygnus;UID=mapx;PWD=mapx"
    Set lyr = Map1.Layers.Add(lif, 1)
    
    ' Add a dataset on the layer
    Set ds = Map1.Datasets.Add(miDataSetLayer, lyr)

    ' Let's determine the number of rows in the dataset.
    nRows = ds.RowCount ' This returns Zero - do not use.
    
    ' A simple way to determine the number of rows in a dataset
    ' is to use the number of features. A dataset contains one

    ' row for each feature in the layer.
    nRows = ds.Layer.AllFeatures.Count ' The number of features
    
    ' This is a more robust method for determining the number of rows.
    ' Since all datasets have one row per feature and we are most likely
    ' trying to determine the number of rows so we can iterate through
    ' the dataset, it is best to use the feature itself or the
    ' feature's key to retrieve a RowValues collection.
    ' Note that AllFeatures on a remote table causes a full scan of

    ' the table and may be slow. Therefore, we do not use syntax
    ' like:
    '   For I = 1 To ds.Layer.AllFeatures.Count
    ' as this will performa full scan every time through the loop.
    ' This is the reason why the RowCount method returns Zero for
    ' a remote table.
    I = 0
    Set ftrs = ds.Layer.AllFeatures
    For Each ftr In ftrs
        Set rv = ds.RowValues(ftr)
        I = I + 1
    Next
    nRows = I
    ' Display the number of rows found in the table

    MsgBox " There are " & nRows & " rows." & Chr(13) & " There are " & ftrs.Count & " features."
    
End Sub