DOC: OLE DB Documentation Inconsistent Returning Nulls

ID: Q196058

The information in this article applies to:

Microsoft OLE DB, version 2.0

SUMMARY

There is inconsistency in the OLE DB 2.0 Programmer's Reference that is included with Visual Studio version 6.0 regarding the value of the length part when a field returns with a status of DBSTATUS_S_ISNULL.

MORE INFORMATION

In Chapter 6, in the topic "Data Transfer Procedures", the following is mentioned with regards to what the provider should do:

   "If it is, the provider sets the status to DBSTATUS_S_ISNULL or VT_NULL,
   sets the length to zero, ignores the value, and proceeds to the next
   column or output parameter."

In Chapter 6, in the subtopic "Status", it states:

   "If the data value is not to be used, the status is set to
   DBSTATUS_S_ISNULL or DBSTATUS_S_DEFAULT. DBSTATUS_S_ISNULL indicates
   that a NULL value is to be used for the column or parameter; the data
   value and length are ignored."

The documentation is corrected in the Microsoft Press OLE DB 2.0 Programmer's Reference. The documentation correction follows:

   "If it is, either the provider sets the status to DBSTATUS_S_ISNULL and
   ignores the value and length or the provider sets the status to
   DBSTATUS_S_OK and sets the value to VT_EMPTY. The provider then proceeds
   to the next column or output parameter."

Additional query words:

Keywords          : kbdocfix kbDatabase kbOLEDB 
Version           : WINDOWS:2.0
Platform          : WINDOWS

Last Reviewed: November 21, 1998