Question-35

Consider the following schedule for transactions \(T1, T2\) and \(T3\):

\(\mathbf{T1}\)	\(\mathbf{T2}\)	\(\mathbf{T3}\)
\(\text{Read}(X)\)
	\(\text{Read}(Y)\)
		\(\text{Read}(Y)\)
	\(\text{Write}(Y)\)
\(\text{Write}(X)\)
		\(\text{Write}(X)\)
	\(\text{Read}(X)\)
	\(\text{Write}(X)\)

Which one of the schedules below is the correct serialization of the above?

• \(T1\rightarrow T3 \rightarrow T2\)
• \(T2\rightarrow T1 \rightarrow T3\)
• \(T2\rightarrow T3 \rightarrow T1\)
• \(T3\rightarrow T1 \rightarrow T2\)

Answer

• \(T1 \rightarrow T3 \rightarrow T2\)
• \(T2 \rightarrow T1 \rightarrow T3\)
• \(T2 \rightarrow T3 \rightarrow T1\)
• \(T3 \rightarrow T1 \rightarrow T2\)