Index: ActiviteitenOpvolging/ActiviteitenOpvolging/mappers/CacheMapper.vb
===================================================================
diff -u -r1677 -r1678
--- ActiviteitenOpvolging/ActiviteitenOpvolging/mappers/CacheMapper.vb	(.../CacheMapper.vb)	(revision 1677)
+++ ActiviteitenOpvolging/ActiviteitenOpvolging/mappers/CacheMapper.vb	(.../CacheMapper.vb)	(revision 1678)
@@ -99,9 +99,12 @@
     Private Function ExtractItemFromDataReader(Of T)(ByRef dr As OdbcDataReader, key As String, Optional defaultValue As T = Nothing) As T
         Dim value As Object
         Try
+            'Check if the column name is not present. If not present, return default value.
+            if not HasColumn(dr, key) Then Return defaultValue
+
             'Extract the value with the key.
             value = dr.Item(key)
-            'Check if the value is DBNull or normal Nothing.
+            'Check if the value is DBNull or Nothing.
             If IsDBNull(value) Or value Is Nothing Then
                 'If so, return default value.
                 Return defaultValue
@@ -117,5 +120,21 @@
         End Try
     End Function
 
+    ''' <summary>
+    ''' Check if the data reader has a column with that name.
+    ''' </summary>
+    ''' <param name="dr"></param>
+    ''' <param name="columnName"></param>
+    ''' <returns></returns>
+    Public Function HasColumn(ByRef dr As OdbcDataReader, columnName As String) As Boolean
+        'Loop through each row.
+        For Each row As DataRow In dr.GetSchemaTable().Rows
+            'Check if column name matches defined one.
+            If row("ColumnName").ToString() = ColumnName Then Return True
+        Next
+        'Column name was not found.
+        Return False
+    End Function
+
 #End Region
 End Module