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Problem accessing dbase III+ files simultaneously with delphi BDE application and a Clipper application

Hi All !!

We are having a big problem when we're accessing dbase III+ files
simultaneously  with BDE and a Clipper application with use RDD CDX
driver ( .idx indexes ): when we run a SQL statement (with TQuery object)
and other users are running this Clipper application, opening and closing
the same DBFS useds by the query, a BDE error occurs:

EDBEngineError :  Read failure.
File or directory does not exist.
File: C:\_QSQL000.DBF
Table does not exist.
Index does not exist.
Index: customer
Lock violation.
File: F:\system\client.dbf

 

Re:Problem accessing dbase III+ files simultaneously with delphi BDE application and a Clipper application


On Fri, 24 Sep 1999 14:38:26 -0300, "Cassio Forti" <cas...@orderby.com.br>
wrote:

Quote
>We are having a big problem when we're accessing dbase III+ files
>simultaneously  with BDE and a Clipper application with use RDD CDX
>driver ( .idx indexes ): when we run a SQL statement (with TQuery object)
>and other users are running this Clipper application, opening and closing
>the same DBFS useds by the query, a BDE error occurs:

>EDBEngineError :  Read failure.
>File or directory does not exist.
>File: C:\_QSQL000.DBF
>Table does not exist.
>Index does not exist.
>Index: customer
>Lock violation.
>File: F:\system\client.dbf

The BDE and Clipper are two totally different database engines. The Clipper
multi-user scheme is not compatible with that of the BDE. Concurrent use of
the same table by both will be problematic. This environment is not
supported by Borland.

_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/
Steve Koterski              "Health nuts are going to feel stupid someday,
Felton, CA                  lying in hospitals dying of nothing."
                                                              -- Redd Foxx

Re:Problem accessing dbase III+ files simultaneously with delphi BDE application and a Clipper application


The BDE  does not share Clipper's locking scheme. You can access
the data with Clipper or with BDE, and switch back and forth, but not
at the same time. (BDE uses .ndx indexes and locking scheme; your
data is using the FoxPro .idx/cdx indexes and locking scheme).

The Apollo database engine replacment was specifically designed (when
Delphi was young and Clipper was showing grey hairs) to allow Delphi
and Clipper to work together simultaneously.

No, I don't work for Vista Software. I didn't even like Apollo all
that much. But if you need Clipper and Delphi to play nice together,
then Apollo is the right tool for the job.

Al

Quote
Cassio Forti wrote:
> Hi All !!

> We are having a big problem when we're accessing dbase III+ files
> simultaneously  with BDE and a Clipper application with use RDD CDX
> driver ( .idx indexes ): when we run a SQL statement (with TQuery object)
> and other users are running this Clipper application, opening and closing
> the same DBFS useds by the query, a BDE error occurs:

> EDBEngineError :  Read failure.
> File or directory does not exist.
> File: C:\_QSQL000.DBF
> Table does not exist.
> Index does not exist.
> Index: customer
> Lock violation.
> File: F:\system\client.dbf

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