How To Create a List of Duplicate Records

 Last reviewed: November 12, 1996
Article ID: Q118294
The information in this article applies to:
  • Microsoft Visual FoxPro for Windows, version 3.0
  • Microsoft FoxPro for MS-DOS, version 2.0, 2.5, 2.5a, 2.5b, 2.6
  • Microsoft FoxPro for Windows, version 2.5, 2.5a, 2.5b, 2.6
  • Microsoft FoxPro for Macintosh, version 2.5b, 2.5c

SUMMARY

This article shows how to generate a list of duplicate records in a database so that you can visually determine what records need to be deleted.

MORE INFORMATION

The following code generates a full list of the duplicate records in INVOICES.DBF and places the list in a cursor named XXX: 

   USE <FoxPro_directory>\tutorial\invoices
   SELECT * FROM invoices WHERE cno IN ;
      (SELECT cno FROM invoices GROUP BY cno HAVING COUNT(cno) > 1) ;
      ORDER BY cno ;
      INTO CURSOR xxx
For information about obtaining the number of duplicate records, please see the following article in the Microsoft Knowledge Base: 

   ARTICLE-ID: Q115617
   TITLE     : How to List Duplicate Records in a Field
For information about deleting duplicate records, please see the following article in the Microsoft Knowledge Base: 

   ARTICLE-ID: Q104332
   TITLE     : Methods of Deleting Duplicate Records from a Database

Additional reference words: VFoxWin 3.00 FoxMac FoxDos FoxWin 2.00 2.50
2.50a 2.50b 2.50c 2.60 identical exact same having clause
KBCategory: kbprg
KBSubcategory: FxprgGeneral

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Last reviewed: November 12, 1996
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