Most banks today use online teller transaction systems. Each transaction is immediately applied to customer accounts to keep balances correct and current. Errors are intolerable, but because of computer failures and power failures, these systems do “go down” occasionally.Describe how you would implement a backup/recovery capability to ensure that each completed transaction applies to the appropriate customer’s account.Also, any transactions only partially completed at the time of a system failure must not apply.
What will be an ideal response?
The transactions would be logged. Before performing anything, mark in the log that a
transaction is about to begin. Then, whenever values are changed, note the old value as well
as the new value.When the transaction is complete,make a mark in the log. If a system crash
occurs, it will be easy to undo the partial transaction by restoring the old values.
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The Startup program will automatically run when a disc is used to ________ software
Fill in the blank(s) with correct word
The Auto-Enhance box, when checked, reduces ________ in the selection boundary.
Fill in the blank(s) with the appropriate word(s).