I know that every conflict-serialisable schedule is view-serialisable but the converse is not true. I read in a webpage that when a schedule is view-serialisable but not conflict-serialisable then there exist some blind writes. So what is a blind write?
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2Perhaps you should cite your source. Or provide excerpts. – Basil Bourque Sep 20 '15 at 4:26
If there is no read that happens prior to the first write then it is said to be a blind write.
Example. Consider the following schedule:
W3(X) is a blind write, as there is no read before write [R3(X) before W3(X)]
W2(X) is not a blind write, as a read happens before write [R2(X) before W2(X)]
A blind write is a write operation e.g. W(X) by a transaction Ti after which the attribute X is not read by a transaction but some other transaction Tj performs another write operation on attribute X. Thus, the write operation by Ti becomes blind write.
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do transactions such as T3 that only contain a blind write ever abort? – Noah Watkins Mar 31 '17 at 20:10
If a transaction without reading a data item directly performs a write operations ,then it is Blind or Dirty Write.
T-1 T-2
R(A)
W(A)
R(A)
W(A)
R(B)
W(B)--------|
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W(B) (In this it has directly performed W(B) without reading
B i.e R(B) )
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