ACC: How to Find Minimum or Maximum Value Across Fields of Record

• Microsoft Access versions 7.0, 97

SUMMARY

Advanced: Requires expert coding, interoperability, and multi-user skills.

Microsoft Access has no built-in functions that find the maximum or minimum values of numbers across the fields of a record. This article shows you how to create two custom functions that cycle through the values across fields and return the minimum or maximum values of each record.

MORE INFORMATION

Microsoft provides programming examples for illustration only, without warranty either expressed or implied, including, but not limited to, the implied warranties of merchantability and/or fitness for a particular purpose. This article assumes that you are familiar with the programming language being demonstrated and the tools used to create and debug procedures. Microsoft support professionals can help explain the functionality of a particular procedure, but they will not modify these examples to provide added functionality or construct procedures to meet your specific needs. If you have limited programming experience, you may want to contact a Microsoft Certified Solution Provider or the Microsoft fee-based consulting line at (800) 936-5200. For more information about Microsoft Certified Solution Providers, please see the following page on the World Wide Web:

http://www.microsoft.com/mcsp/

http://www.microsoft.com/support/supportnet/overview/overview.asp

1. Open a new module and enter the following two functions:




      Function Minimum(ParamArray FieldArray() As Variant)
         ' Declare the two local variables.
         Dim I As Integer
         Dim currentVal As Variant

         ' Set the variable currentVal equal to the array of values.
         currentVal = FieldArray(0)

         ' Cycle through each value from the row to find the smallest.
         For I = 0 To UBound(FieldArray)
            If FieldArray(I) < currentVal Then
               currentVal = FieldArray(I)
            End If
         Next I

         ' Return the minimum value found.
         Minimum = currentVal

      End Function

      Function Maximum(ParamArray FieldArray() As Variant)
         ' Declare the two local variables.
         Dim I As Integer
         Dim currentVal As Variant

         ' Set the variable currentVal equal to the array of values.
         currentVal = FieldArray(0)

         ' Cycle through each value from the row to find the largest.

         For I = 0 To UBound(FieldArray)
            If FieldArray(I) > currentVal Then
               currentVal = FieldArray(I)
            End If
         Next I

         ' Return the maximum value found.
         Maximum = currentVal

      End Function 

2. On the Debug menu, click Compile And Save All Modules. Then close the module.



3. Create the following table named tblMinMax:




      Table: tblMinMax
      ---------------------------
      Field Name: Field1
         Data Type: Number
         Field Size: Long Integer
      Field Name: Field2
         Data Type: Number
         Field Size: Long Integer
      Field Name: Field3
         Data Type: Number
         Field Size: Long Integer 

4. Save the table as tblMinMax. When prompted to create a primary key, click No.



5. Switch the tblMinMax table to Datasheet view and enter the following values:




      Field1    Field2    Field3
      ------    ------    ------

      50        30        40
      40        50        30
      30        40        50 

6. Create a new query based on the tblMinMax table and drag Field1, Field2, and Field3 to the query grid.



7. In the fourth column of the query grid, enter the following expression:




Minimum Value: Minimum([Field1],[Field2],[Field3])

8. In the fifth column of the query grid, enter the following expression:




Maximum Value: Maximum([Field1],[Field2],[Field3])

9. Run the query. Note that the fourth and fifth columns contain the minimum and maximum values.

REFERENCES

For more information about creating custom functions, search the Help Index for "custom functions", and then "Create a Custom Function."

Additional query words: inf Min Max DMin DMax Largest Smallest

Keywords : kbdta kbdtacode PgmHowto
Version : WINDOWS:7.0,97
Platform : WINDOWS
Issue type : kbhowto