week 9 . 9.1.1 first level pass task PDF

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week 9 pass task which is important to pass the unit....

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T1 If we consider this table T1, it can be issued or given out as a one single transaction or three separate ones. The reason for that is that T1 read out the table that is been modified by the Transaction T2, therefore the T1 transaction does not affect the table in any way.

T2 In here the transaction is due to the ACID principle. So this transaction refers to the A and D in which is Atomicity and Durability. Where atomicity is the transaction taking place is its own unit work. This limits all the commands within the transaction to one specific task where it alter the tables which is required and places them in right order. When is comes to durability the database which is given would be inconsistent if T2 here is not a transaction. In durability the database must maintain integrity and coherent....