Which of the following violates the rules of First Normal Form (1NF)?
2025
Which of the following violates the rules of First Normal Form (1NF)?
- A.
A row with a column storing multiple email addresses as a comma-separated list
- B.
A column with NULL values
- C.
A column that stores phone numbers as VARCHAR
- D.
A table with a composite primary key
Attempted by 217 students.
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Correct answer: A
First Normal Form (1NF) requires that each column in a table must contain atomic (indivisible) values and there should be no repeating groups or multiple values stored in a single column.
A column storing multiple email addresses as a comma-separated list violates 1NF because one field contains multiple values instead of a single atomic value.