Q192862: BUG: Incorrect Return of SubSelect in SELECT-SQL Statement

Article: Q192862
Product(s): Microsoft FoxPro
Version(s): WINDOWS:3.0,3.0b,5.0,5.0a,6.0
Operating System(s): 
Keyword(s): 
Last Modified: 11-DEC-1999

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, versions 3.0, 3.0b, 5.0, 5.0a, 6.0 
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SYMPTOMS
========

A SQL Select using the Not In clause with a subquery might incorrectly return no
records.

RESOLUTION
==========

Use a user defined function in the subselect similar to the example below:

      SELECT * FROM orders WHERE order_id NOT IN ;
         (SELECT order_id FROM orditems WHERE MyFunction(order_id))

      FUNCTION MyFunction
         LPARAM lx
         RETURN .F.
      ENDFUNC

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article.

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

In the following cases, the main query could return an incorrect number of
records:

     SELECT * FROM orders WHERE order_id NOT IN ;
        (SELECT order_id FROM orditems WHERE 1=2)

  -or-

     SELECT * FROM orders WHERE order_id NOT IN ;
        (SELECT order_id FROM orditems WHERE .F.)

The above queries return 0 records rather than all records in the table.

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

1. Open the TestData Sample Database.

2. Run one of the SQL Select statements listed in the MORE INFORMATION section
  of this article.

3. Notice that the Select returns no rows.

Additional query words: kbDSupport KBDSE kbVFp300bbug kbVFp500abug kbVFp600bug kbSQL

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Keywords          :  
Technology        : kbVFPsearch kbAudDeveloper kbVFP300 kbVFP300b kbVFP500 kbVFP600 kbVFP500a
Version           : WINDOWS:3.0,3.0b,5.0,5.0a,6.0
Issue type        : kbbug

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