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a)   S with no dirty read then S is cascadeless rollback but may not be strict recoverable
b)   S with no dirty read then S is recoverable but  may not be cascadeless rollback
c)   S with no dirty read then S is conflict serializable schedule
d)   S with no dirty read then S is strict recoverable
 

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c)??
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In the test series,answer given is (a) with no explanation

For (c) counter example is:

S: R1(x),R2(x),w2(x),c2,w1(x),c1 has no dirty read but it is not CS

Please correct me if I am wrong
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what is strict recoverable schedule? Is it strict schedule or Recoverable schedule?It is only recoverable, right?
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strict recoverable

From best answer of this question, i think strict recoverable means a strict schedule

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no, Strict schedule must be cascadeless too. So, it should be recoverable.

By the way, can you show mw the answer once?
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S: R1(x),R2(x),w2(x),c2,w1(x),c1 has no dirty read but it is not CS

this is non-atomic. right? but question is about atomic transaction 

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Strict schedule must be cascadeless too. So, it should be recoverable.
 

i have read that "all strict schedule is cascadeless  but all schedules with cascadeless rollback is not strict".since strict schedule is subset so if strict recoverable were to mean strict schedule then there are cases where a schedule is cascadeless but not strict recoverable

is my reasoning correct?

also i have posted the answer

 

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this is non-atomic. right? but question is about atomic transaction

 my mistake.i didn't see this clearly.i have a doubt here also  -- if transactions were to be atomic then does it mean that schedule is always serial or it can also occur in concurrent schedules ?

+1
Again another unclear word in this question...

i.e."cascadeless rollback." There is nothing like this, either it will be cascading rollback or cascadless schedule.

So, I think, we shouldnot think more on this question..

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