This macro marks as duplicates any records that have the same value in a field as the first record with that value. This macro illustrates how to:

  1. Loop over the records in sorted order
  2. Read a value from a field
  3. Find the first record in a group
  4. Write a value to a field

You can modify the macro to use a dialog box to get the values for the input variable, mark members of a group with a counter (1, 2, 3, etc.), add the duplicates to a selection set, etc.


  1. Download the file GISDK_Mark and extract the file MARK DUPLICATES.RSC. A good place to save the resource file is in the GISDK\Samples folder in the Maptitude program folder.
  2. Open the table that you want to use and get the name of the dataview.
  3. Edit the initialization section to set the values of the variables and save the changes.
  4. Choose Tools-GIS Developer's Kit-GISDK Toolbar to open the GISDK toolbar.
  5. Compile this macro in test mode using the Compile button (first button).
  6. Run this macro by clicking the Test button (second button), typing the macro name (Mark Duplicates), clicking the Macro radio button, and clicking OK.