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A primary key is a critical concept in relational databases, ensuring that each record within a table can be uniquely identified. The primary key has the following key characteristics: • Uniqueness: Each value of a primary key must be unique across the entire table. No two rows can have the same primary key value. • Non-nullable: A primary key must always have a value; it cannot be null. This is essential for maintaining the integrity of the database as it ensures that every record can be uniquely identified.
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Which of the following is true regarding F?
What is the position of X with respect to T?
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What is the position of C with respect to the one who likes Black?
Who among the following sit at extreme ends of the rows?
Seven persons, R, S, T, U, V, W and X, sit along a linear row. All face in the south direction. T sits along the middle of the row. W sits second to the...
Who among the following person sits second to the right of C?