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The ACID properties are Atomic, Consistency, Isolation, Durability.
Atomic means that the operation happens in once and will not stop at a middle point. When there is something wrong with the operation, it will rollback to the beginning like the operation never happens.
Consistency means that the database is consistent before and after the operation, if it successes, it will adapt the changes in a correct way. If it fails, the changes will rollback. Isolation means that the intermediate state of a transaction not transparent to other transactions. Other transaction will only see the database before or after each transaction. When multiple operations happens to the database, it prevents the data from mistakes. Durability means that after the transaction success, the updated version of database will be preserved. Even if the system collapses and restart, the database still remain the status after the transaction success.
1 False, because when A3 = 1, A1 can be either A1 = a or A1 = d.
2 True, because every value in A1 decides a value in A3
3 False, because when A2 = p, A3 can be either A3 = 1, A3 = 2 or A3 = 4 4 True, because {A1, A2} uniquely decide {A1, A2}
5 True, because A1 decides A3, hence {A1, A2} decides A3
Not in 3NF, because there exists transitively dependent on the PRIMARY KEY, To solve this we decompose the table into two tables
S1 (B1, B2, B3. B4, B5) and S2(B5, B6)
The functional dependency stay un-changed
In this manner, the transitively dependent is broke
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