If you’re using Microsoft Excel to capture and track data, one of the challenges is maintaining good data quality when more than one person is updating the workbook. The data validation features in Excel help by allowing the user to select data based on pre-defined options in a list. This feature works well on individual cells. However, if you have a column that depends on the value in a different column, you will need to get a little more creative. This post describes the steps for creating cascading drop-down lists in Excel using a combination of data validation and named ranges.
Step 1 – Define the Reference Data
Let’s assume that you are collecting data that includes Organization and Department attributes. In this example, an Organization is the parent to one or more Departments. We’ll set up the reference data for the data validation drop-down lists as follows on its own worksheet.
- Column A (“ORGANIZATION”) represents the list of valid Organizations that will appear in the Organization drop-down list.
- Column B (“NAMED RANGE MAPPING”) represents the names given to ranges that will be defined in a later step.
- Columns D through E (“ORG_X_DEPARTMENTS”) represent the lists of valid Departments that will appear in the Department drop-down list depending upon which Organization is selected.
Step 2 – Define the Named Ranges
Now that we have the reference data established, we can define the named ranges that refer to these lists. The named range entry defined as ORGS_TO_DEPTS_MAPPINGS is the key to creating the cascading drop-down list functionality. It is important that the values in Column B match the names given to the ORG_X_DEPARTMENTS ranges. This value will be used in a subsequent step with an indirect and vlookup data validation formula.
Step 3 – Define the Organization Data Validation (Parent Column)
In this step, we establish the standard data validation on the parent data in Column A (“ORGANIZATIONS”) on a new data collection worksheet.
Step 4 – Define the Department Data Validation (Child / Dependent Column)
Here we establish the data validation rule that performs the cascading drop-down list function. Once the user selects a valid Organization, this formula performs a vlookup against the ORGS_TO_DEPTS_MAPPINGS named range and returns the name of the Department named range associated with the selected Organization. The indirect function then converts that name, a text value, into the range reference.
When you click the OK button, Excel will display the following error message. Click the Yes button to continue.
Step 5 – Test the Cascading Drop-down Lists
Now that the data validation rules are set up, we can test the cascading drop-down list functionality. Selecting “Org 1” will cause the validation drop-down list in the Department column to reflect only those Departments associated with “Org 1”. Selecting “Org 2” causes the Department drop-down list to show those Departments associated with “Org 2”.
Step 6 – Macro to Validate Parent / Dependent Relationship
Now that the worksheet is functioning as expected, you release it for users to update and someone will inevitably enter data in a way that breaks the parent / dependent relationship. As an example, “Org 1” is selected in the Organization column and “Dept 1” is selected in the Department column. The user then returns to the Organization column and changes the entry to “Org 2”. The Department column retains the value of “Dept 1” which is not valid for the “Org 2” selection in the Organization column. To help avoid these errors, you can save the file as a macro enabled workbook and add the following code to the data entry worksheet. If this macro had been enabled, the “Dept 1” value would have been removed as soon as the user selected “Org 2”. This code assumes that the parent column is the first column (Column A) in the worksheet and the dependent column is immediately to the right (Column B). Please revise the code to meet your specific requirements.
Option Explicit
Private Sub Worksheet_Change(ByVal Target As Range)
On Error GoTo exitHandler
With Application
.EnableEvents = False
.ScreenUpdating = False
End With
If Target.Column = 1 Then
If Target.Validation.Type = xlValidateList Then
If Not Target.Offset(0, 1).Validation.Value Then
Target.Offset(0, 1).ClearContents
End If
End If
End If
exitHandler:
With Application
.EnableEvents = True
.ScreenUpdating = True
End With
End Sub
