Consider a system using two-phase locking at a singlegranularity (no intention locks), and a particular execution duringwhich the edge Ti → Tk appears at some point in the wait-for graph,but the edge Tk → Ti never appears in the wait-for graph. Assumethat both Ti and Tk eventually commit.
(a) It is necessary that the precedence graph contain the edgeTi → Tk? Explain.
(b) It is necessary that the precedence graph contain the edgeTk → Ti? Explain.
Solution