Transaction failure
– There are two types of errors that may
cause a transaction to fail:
• Logical error.
– The transaction can no longer continue with its
normal execution because of some internal
condition, such as bad input, data not found,
overflow, or resource limit exceeded.
• System error.
– The system has entered an undesirable state (for
example, deadlock), as a result of which a
transaction cannot continue with its normal
execution. The transaction, however, can be
reexecuted at a later time.