Consider the following four schedules due to three transactions (indicated by the subscript) using read and write on a data item x, denoted by $r(x)$ and $w(x)$ respectively. Which one of them is conflict serializable?
(D) make precedence graph for all the options, for option (D) only graph will be acyclic, hence (D) is CSS.
take node for evry transaction
procedure is simple scan left to right for
take first element => scan from 2nd elemnt to right for every r-w . w-w or w-r conflict in diffrent transaction thier is a edge
take 2nd element => scan from 3rd elemnt to right for every r-w . w-w or w-r conflict in diffrent transaction thier is a edge
do like this skip left side one elemnt evry time.
if u found cycle then not css otherwise css.
When will be the final official key...