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Question

Which of the following scenarios may lead to an irrecoverable error in a database system ?

a.

A transaction writes a data item after it is read by an uncommitted transaction

b.

A transaction reads a data item after it is read by an uncommitted transaction

c.

A transaction reads a data item after it is written by a committed transaction

d.

A transaction reads a data item after it is written by an uncommitted transaction

Answer: (d).A transaction reads a data item after it is written by an uncommitted transaction

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Q. Which of the following scenarios may lead to an irrecoverable error in a database system ?

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