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CDaoRecordset::IsFieldNullable

Call this member function to determine whether the specified field data member is "nullable" (can be set to a Null value; C++ NULL is not the same as Null, which, in database terminology, means "having no value").

BOOL IsFieldNullable(
   void* pv 
);

Parameters

  • pv
    A pointer to the field data member whose status you want to check, or NULL to determine if any of the fields are Null.

Return Value

Nonzero if the specified field data member can be made Null; otherwise 0.

Remarks

A field that cannot be Null must have a value. If you attempt to set such a field to Null when adding or updating a record, the data source rejects the addition or update, and Update will throw an exception. The exception occurs when you call Update, not when you call SetFieldNull.

Requirements

Header: afxdao.h

See Also

Concepts

CDaoRecordset Class

CDaoRecordset Members

Hierarchy Chart

CDaoRecordset::IsFieldDirty

CDaoRecordset::IsFieldNull