Il WHERE VA DOPO IL FROM

dataAdapter1 = New SqlCeDataAdapter("SELECT Sum(ferie.Giorni where ferie.Altro =" & "F" & ")Prese FROM ferie", cn1)
commandBuilder1 = New SqlCeCommandBuilder(dataAdapter1)
dataSet1 = New DataSet
dataAdapter1.Fill(dataSet1)
DataGrid5.DataSource = dataSet1.Tables(0)