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3 votes
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Why is Blind write necessary for a view serializable schedule that is not conflict serializable?
in Databases
edited by
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2 Answers

0 votes
> If it's conflict serializable then it's also view serializable.

> If not Conflict serializable then:

   {

               If there is Blind Write then check if View Serializable or not.

               If there is no Blind Write then definitely not View Serializable.

   }
–1 vote
It is not necessary condition for view serializable, only if u find a schedule which is not conflict serializable u go for checking whether it is view serializable or not . If Blind write is there then it may or may not be view serializable.
1

From the textbook by Silberschatz:

Blind writes appear in any view-serializable schedule that
is not conflict serializable.

Does this mean if it is a view serializable schedule but not conflict serializable, then it must have a blind write? Is the word 'any' above replaceable by 'all' without changing the meaning of the sentence?

0
Thanks, that not only cleared my doubt, but also the doubt that followed from it  :)

"Are there conflict serializable schedules that contain blind writes?" The answer is yes.
1

Does this mean if it is a view serializable schedule but not conflict serializable, then it must have a blind write?

yes

 

Is the word 'any' above replaceable by 'all' without changing the meaning of the sentence?

yes

 

"Are there conflict serializable schedules that contain blind writes?

yes

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