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Q161498: FIX: Full Outer Join Returns No Records If One Table is Empty

Article: Q161498
Product(s): Microsoft FoxPro
Version(s): WINDOWS:5.0
Operating System(s): 
Keyword(s): kbprogramming kbvfp kbvfp500aFIX kbvfp500bugkbbuglist kbfixlist
Last Modified: 04-FEB-2000

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, version 5.0 
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SYMPTOMS
========

The Full Outer Join SQL-SELECT command returns an empty result set when one of
the tables or cursors is empty.

STATUS
======

Microsoft has confirmed this to be a problem in the Microsoft products listed at
the beginning of this article. This problem has been fixed in Visual FoxPro
5.0a.

MORE INFORMATION
================

The Full Outer Join should return all the records from both tables or cursors.
If one file is empty, then a Full Outer Join should return all the records from
the other table.

Steps to Reproduce Behavior
---------------------------

Create a program file and add the following code:

     CREATE CURSOR cur1 (id_1 I(4), desc_1 C(20))
     CREATE CURSOR cur2 (id_2 I(4), desc_2 C(20))
     ** Places 10 records in cur1
     FOR l_n = 1 TO 10
        INSERT INTO cur1 (id_1, desc_1) VALUES (l_n, "TABLE1__"  + ;
         ALLTRIM(STR(l_n)))
     ENDFOR
     ** Performs full outer join
     SELECT * FROM cur1 FULL OUTER JOIN cur2 ON id_1 = id_2

The Browse window displays an empty result set.

Additional query words:

======================================================================
Keywords          : kbprogramming kbvfp kbvfp500aFIX kbvfp500bug kbbuglist kbfixlist
Technology        : kbVFPsearch kbAudDeveloper kbVFP500
Version           : WINDOWS:5.0
Issue type        : kbbug
Solution Type     : kbfix

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