The
IsDBNull method tests whether the value parameter is equal to
DBNull.Value
& returns an indication whether the specified object is of type
DBNull
.
The
System.DBNull
value indicates that the Object represents missing or nonexistent data.
DBNull
is not the same as Nothing, which indicates that a variable has not yet been initialized.
DBNull
is also not the same as a zero-length string (""), which is sometimes referred to as a null string.
DBNull
returns True if the data type of Expression evaluates to the DBNull type; otherwise, IsDBNull returns False.
IsNull
Replaces NULL with the specified replacement value.
Please refer:
ISNULL (Transact-SQL)[
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Additional info:
Learn the differences between Is Null and IsNull()[
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