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Q190496: PRB: SEEK Finds Old and New Data With Optimistic Buffering

Article: Q190496
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
========

When you use the SEEK command to find data and then replace that data with
another value, SEEK finds both the old value and the new value if the buffering
is set to optimistic table buffering.

RESOLUTION
==========

Set the buffering to optimistic row buffering or pessimistic buffering.

STATUS
======

Microsoft has confirmed this to be a problem in the Microsoft products listed at
the beginning of this article. We are researching this problem and will post new
information here in the Microsoft Knowledge Base as it becomes available.

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

The Customer table, used in the Sample Code example, ships as sample data in
Visual FoxPro 3.0x, 5.0x, and 6.0. Before running the program, use the SET
DEFAULT TO command to point to the folder that contains the Customer table.

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

Issue the following commands in the Command window or create a .prg file and run
the program.

Sample Code
-----------

     SET MULTILOCKS ON
     USE customer
     =CURSORSETPROP('Buffering',5)
     SET ORDER TO cust_id
     ?SEEK('AROUT')
     REPLACE CUST_ID WITH 'AROUS'
     ?SEEK('AROUT')
     ?SEEK('AROUS')

Note that the SEEK function returns true for the old value "AROUT" and for the
new value "AROUS". Setting the buffering to optimistic row buffering or to
pessimistic buffering, allows the SEEK function to find only the new value.

Additional query words: kbVFp300b kbVFp300 kbVFp500 kbVFp500a kbVFp600 kbXBase

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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        : kbprb
Solution Type     : kbpending

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