Consider a database with a Table A(x) containing integers. Adam runs a query (that is a transaction): Select sum(x) from A; Commit; Brandon consider a sequence of inserts (this is also a transaction): Insert into A values (10); Insert into A values (20); Insert into A values (30); Commit; Christopher consider a sequence of deletes (this is also a transaction): Delete from A where x=30; Delete from A where x=20; Commit; a) At the beginning, before executing any transaction, the sum of the integers in A is 1000 and none of them are 10, 20, or 30. If all transactions (run under isolation level READ SERIALIZABLE) run at about the same time, what are the possible sums that can be produced by Adam's transaction? b) At the beginning, before executing any transaction, the sum of the integers in A is 1000 and none of them are 10, 20, or 30. If all transactions (run under isolation level READ UNCOMMITTED) run at about the same time, what are the possible sums that can be produced by Adam's transaction?

Problem4 Consider a database with a Table A(x) containing integers. Adam runs a query (that is a transaction): Select sum(x) from A Commit; Brandon consider a sequence of inserts (this is also a transaction) Insert into A values (10); Insert into A values (20); Insert into A values (30); Commit; Christopher consider a sequence of deletes (this is also a transaction): Delete from A where x-30; Delete from A where x-20; Commit; At the beginning, before executing any transaction, the sum of the integers in A is 1000 and none of them are 10, 20, or 30. If all transactions (run under isolation level READ SERIALIZABLE) run at about the same time, what are the possible sums that can be produced by Adam's transaction? a) b) At the beginning, before executing any transaction, the sum of the integers in A is 1000 and none of thenm time, what are the possible sums that can be produced by Adam's transaction