DOCUMENT:Q155936  24-AUG-1999  [foxpro]
TITLE   :PRB: Closing Table Loses Changes with Table Buffering
PRODUCT :Microsoft FoxPro
PROD/VER:5.00
OPER/SYS:
KEYWORDS:kbvfp500 kbvfp600

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The information in this article applies to:

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

If you use a CLOSE or USE command to close an open table, and that table uses
Table Buffering and contains uncommitted changes, Visual FoxPro closes the table
and does not save the uncommitted changes. Additionally, no error dialog box
appears when you close the table. This behavior is different from Visual FoxPro
versions 3.0 and 3.0b, which displays an error dialog box if you attempt to
close a table with uncommitted changes.

WORKAROUND
==========

Use the TABLEUPDATE() function to force Visual FoxPro to save the changes before
closing the table.

STATUS
======

This behavior is by design.

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

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

The following example uses the Customer table in the Visual FoxPro
Samples\Data\Testdata database:

1. Run the following code from a program:

      *  Start of code example

      LOCAL nI
      CLOSE DATABASES ALL
      FOR nI = 1 TO 5
         USE HOME() + 'samples\data\customer'
         =CURSORSETPROP('buffering',nI)
         REPLACE company WITH ALLTR(company) + ' ' + ALLTRIM(STR(nI))
         SKIP
         USE          && Closes table
         USE HOME() + 'samples\data\customer'
         BROWSE
      ENDFOR
      REPLACE company WITH SUBSTR(company,1,ATC('1',company,1)-1)

      *  End

   Notice the numeral appended after the company name in the first record, and
   then close the Browse window. Do this for each of the five times the Browse
   window appears. The numbers 1 through 3 appear, but 4 and 5 do not. Number 1
   is no buffering, 2 and 3 are Pessimistic and Optimistic Row buffering, and 4
   and 5 are Pessimistic and Optimistic Table buffering.

2. As a workaround for the above example, modify the above code as follows:

      *  Start of code example

      LOCAL nI
      CLOSE DATABASES ALL
      FOR nI = 1 TO 5
         USE HOME() + 'samples\data\customer'
         =CURSORSETPROP('buffering',nI)
         REPLACE company WITH ALLTRIM(company) + ' ' + ALLTRIM(STR(nI))
         SKIP
         * The following statement is necessary to prevent errors
         * with GETNEXTMODIFIED() if table buffering is not used
         IF CURSORGETPROP('buffering') > 3

           IF GETNEXTMODIFIED(0) > 0    && Checks for any modified records

             =TABLEUPDATE(1)            && Or whatever you want to do
                                        && before you close the table
           ENDIF
         ENDIF
         USE                            && Closes table
         USE HOME() + 'samples\data\customer'
         BROWSE
      ENDFOR
      REPLACE company WITH SUBSTR(company,1,ATC('1',company,1)-1)

      *  End

   The changed record is saved, even when table buffering is used.

REFERENCES
==========

Visual FoxPro 5.0 Help file; search on: "CURSORSETPROP()," "GETNEXTMODIFIED(),"
and "TABLEUPDATE()"

Visual FoxPro 5.0 Readme.hlp file; search on: "Using Visual FoxPro," then
"Closing a Cursor with an Uncommitted Record"

Additional query words: kbdse VFoxWin

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Keywords          : kbvfp500 kbvfp600 
Technology        : kbVFPsearch kbAudDeveloper kbVFP500 kbVFP600
Version           : 5.00

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