KnowledgeBase Archive

An Archive of Early Microsoft KnowledgeBase Articles

View on GitHub

Q129168: How to Recover Corrupt DataBase Container Files

Article: Q129168
Product(s): Microsoft FoxPro
Version(s): 3.00
Operating System(s): 
Keyword(s): 
Last Modified: 13-AUG-1999

-------------------------------------------------------------------------------
The information in this article applies to:

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

SUMMARY
=======

The best way to ensure that you will be able to recover corrupt DBC files is to
use proactive measures, such as frequently backing up the Database files (both
the .DBC and .DCT files). The next best method is to use the GENDBC.PRG tool
located in the VFP\TOOLS\GENDBC subdirectory.

GENDBC.PRG is a utility that generates a custom .PRG file that can then be
executed to re-build the DataBase Container that GENDBC was run against. The
resulting .PRG file, when run, will recreate the DataBase Container to the state
prior to when GENDBC was run against it. Thus it may be necessary to run GENDBC
many times during the development life cycle to prevent loss of work if the
files are damaged.

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

When GENDBC.PRG is run, it creates a "generation" program file for the current
Database container. If no Database is open it will prompt for one.

To use GENDBC, execute it from the Command window. For example:

     DO C:\VFP\TOOLS\GENDBC\GENDBC.PRG WITH 'GD_MYDBC'

When GENDBC.PRG is finished, a program file with the same name as the database
will be created in the current directory. This program can then be executed to
recreate damaged Database (.DBC) files. For instance, in the example above, a
program named "GD_MYDBC.PRG" would be created.

If the Database (.DBC) file is corrupt or damaged at the table level (in other
words, the .DBC is a FoxPro Table (.DBF)) and it is not usable as a FoxPro
table, GENDBC will not correct the matter. The error generated in this case is:

  UNRECOVERABLE ERROR...FILE <path>\dbc_name.dbc
  IS NOT A DATABASE AT LINE <line_no>

If this is the case, a third-party database repair utility will be required to
repair the DBC at the table level. However, once the file is corrected in this
manner, there is still no guarantee that the .DBC file will be recoverable with
GENDBC.PRG. Thus the importance of using GENDBC.PRG prior to using the Database
or immediately following any changes to the Database Container.

For additional information on repairing a corrupt database, please see the
following article in the Microsoft Knowledge Base:

  Q129400 Free Table Command Removes Table From Corrupted Database

Additional query words: VFoxWin remove free damage corrupted

======================================================================
Keywords          :  
Technology        : kbVFPsearch kbAudDeveloper kbVFP300
Version           : 3.00

=============================================================================

THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY.