DOCUMENT:Q140579  24-MAR-2000  [foxpro]
TITLE   :FIX: Incorrect Results from SELECT with Nested SELECTs and OR
PRODUCT :Microsoft FoxPro
PROD/VER:WINDOWS:3.0
OPER/SYS:
KEYWORDS:kbbuglist kbfixlist

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The information in this article applies to:

 - Microsoft Visual FoxPro for Windows, version 3.0 
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SYMPTOMS
========

A SELECT statement with two nested SELECTs connected by an OR may return
incorrect results depending on which tables are open in which work areas before
the select is run.

STATUS
======

Microsoft has confirmed this to be a problem in the Microsoft products listed at
the beginning of this article. This problem was corrected in Microsoft Visual
FoxPro 3.0b for Windows.

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

Steps to Reproduce Problem
--------------------------

1. Create three tables named Test1, Test2, and Test3. Place the following
   information in each table:

   Table Test1 has one field (char1) containing these records:

      AAAAA
      BBBBB
      CCCCC
      DDDDD
      EEEEE
      FFFFF
      GGGGG
      HHHHH

   Table Test2 has two fields (Char1 and Char2) containing these records:

      char1    char2
      AAAAA    ZZZZZ
      ZZZZZ    AAAAA
      YYYYY    WWWWW
      BBBBB    VVVVV
      UUUUU    CCCCC
      WWWWW    PPPPP
      VVVVV

   Table Test3 has one field (char1) with one record containing:

      qqqqq

2. Run the following program, and notice that the results of the query vary
   depending on which tables are open and which work areas they are using:

      CLOSE DATA
      USE test1 IN 1
      SELECT char1 FROM test1 WHERE ;
        char1 IN (SELECT char1 from test2) OR ;
        char1 IN (SELECT char2 from test2) ;
        INTO CURSOR query
      BROWSE TITLE 'Test1 open in WA1'   && returns all records from test1

      CLOSE DATA
      USE test3
      SELECT char1 FROM test1 WHERE ;
        char1 IN (SELECT char1 FROM test2) OR ;
        char1 IN (SELECT char2 FROM test2) ;
        INTO CURSOR QUERY
      BROWSE TITLE 'Test3 open in WA1'   && returns all records from test1

      CLOSE DATA
      USE test1 IN 2
      SELECT char1 FROM test1 WHERE ;
        char1 IN (SELECT char1 FROM test2) OR ;
        char1 IN (SELECT char2 FROM test2) ;
        INTO CURSOR QUERY
      BROWSE TITLE 'Test1 open in WA2' && returns correct records from test1

      CLOSE DATA
      SELECT char1 FROM test1 WHERE ;
        char1 IN (SELECT char1 FROM test2) OR ;
        char1 IN (SELECT char2 FROM test2) ;
        INTO CURSOR QUERY
      BROWSE TITLE 'No tables open'   && returns correct records from test1

      SELECT char1 FROM test1 WHERE ;
        char1 IN (SELECT char1 FROM test2) or ;
        char1 IN (SELECT char2 FROM test2) ;
        INTO CURSOR QUERY
      BROWSE TITLE 'Test1 in WA1 and Test2 in WA2'   && returns no records

Additional query words: VFoxWin fixlist3.0b buglist3.00

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Keywords          :  kbbuglist kbfixlist
Technology        : kbVFPsearch kbAudDeveloper kbVFP300
Version           : WINDOWS:3.0
Issue type        : kbbug
Solution Type     : kbfix

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