DOCUMENT:Q131031 15-FEB-2000 [foxpro] TITLE :READ NOLOCK Behavior in Visual FoxPro PRODUCT :Microsoft FoxPro PROD/VER:WINDOWS:3.0 OPER/SYS: KEYWORDS:kbnetwork ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Visual FoxPro for Windows, version 3.0 ------------------------------------------------------------------------------- SUMMARY ======= The behavior of the READ NOLOCK command in Visual FoxPro is slightly different from its behavior in FoxPro version 2.x. MORE INFORMATION ================ READ NOLOCK alters the behavior of the READ command, so records are not automatically locked by the READ. In FoxPro version 2.x, issuing a READ NOLOCK command automatically disables all fields. Attempts to key data into the fields causes a high-pitched beep until a SHOW GETS LOCK command is issued. In Visual FoxPro, the beep is no longer heard. Instead, a "Record is read only" message appears on the status bar. A SHOW GETS LOCK command is still required to edit the fields. If buffering is enabled, the READ NOLOCK command overrides the locking behavior of the buffering mode that is in effect. If pessimistic locking is enabled, the record is not locked until the SHOW GETS LOCK command is issued. If optimistic locking is enabled, the record is locked at the time the SHOW GETS LOCK is issued, not at the time the record is written to disk. The TABLEUPDATE() and TABLEREVERT() commands should not be used in conjunction with READ NOLOCK. You should modify the application to use buffering completely or to use READ NOLOCK without enabling buffering. Additional query words: VFoxWin ====================================================================== Keywords : kbnetwork Technology : kbVFPsearch kbAudDeveloper kbVFP300 Version : WINDOWS:3.0 ============================================================================= 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. Copyright Microsoft Corporation 2000.