The error message Index or primary key cannot contain a Null Value. will be generated by attempting which of the following?
A) A user tries to enter a record in the table Countries that doesn't contain data in the primary key.
B) A user tries to add a record to a table that is related to the Countries table, and that record contains a foreign key value that does NOT correspond to a primary key value in the Countries table.
C) A user tries to enter a record in the table Countries with the same primary key as another record.
D) A user tries to request a joined table using LINQ.

Question

Quizplus · Accepted Answer

The error message "Index or primary key cannot contain a Null Value" is typically generated when trying to insert a record into a table and one of the fields that has been defined as a primary key or that is used in an index has been left blank, which violates the rule that primary keys cannot contain null values.

The Error Message Index or Primary Key Cannot Contain a Null