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CDaoRecordset::SetLockingMode

Call this member function to set the type of locking for the recordset.

void SetLockingMode( 
   BOOL bPessimistic  
);

Parameters

  • bPessimistic
    A flag that indicates the type of locking.

Remarks

When pessimistic locking is in effect, the 2K page containing the record you are editing is locked as soon as you call the Edit member function. The page is unlocked when you call the Update or Close member function or any of the Move or Find operations.

When optimistic locking is in effect, the 2K page containing the record is locked only while the record is being updated with the Update member function.

If a page is locked, no other user can edit records on the same page. If you call SetLockingMode and pass a nonzero value and another user already has the page locked, an exception is thrown when you call Edit. Other users can read data from locked pages.

If you call SetLockingMode with a zero value and later call Update while the page is locked by another user, an exception occurs. To see the changes made to your record by another user (and lose your changes), call the SetBookmark member function with the bookmark value of the current record.

When working with ODBC data sources, the locking mode is always optimistic.

Requirements

Header: afxdao.h

See Also

Reference

CDaoRecordset Class

Hierarchy Chart

CDaoRecordset::GetLockingMode