Consider the following transactions with data items P and Q initialized to zero : T1 : read (P); read (Q); if P = 0 then Q = Q + 1; write (Q); T2 : read (Q); read (P); if Q = 0 then P = P + 1; write (P); Any non-serial interleaving of T1 and T2 for concurrent execution leads to

a conflict serializable schedule

a schedule that is not conflict serializable

a conflict serializable schedule

a schedule for which a precedence graph cannot be drawn

Consider the following transactions with data items P and Q initialize

1.	Consider the following transactions with data items P and Q initialized to zero : T1 : read (P); read (Q); if P = 0 then Q = Q + 1; write (Q); T2 : read (Q); read (P); if Q = 0 then P = P + 1; write (P); Any non-serial interleaving of T₁ and T₂ for concurrent execution leads to
A.	a serializable schedule
B.	a schedule that is not conflict serializable
C.	a conflict serializable schedule
D.	a schedule for which a precedence graph cannot be drawn
Answer» C. a conflict serializable schedule

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Consider the following transactions with data items P and Q initialized to zero : T1 : read (P); read (Q); if P = 0 then Q = Q + 1; write (Q); T2 : read (Q); read (P); if Q = 0 then P = P + 1; write (P); Any non-serial interleaving of T1 and T2 for concurrent execution leads to

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Consider the following transactions with data items P and Q initialized to zero :
T1 : read (P);
read (Q);
if P = 0 then Q = Q + 1;
write (Q);
T2 : read (Q);
read (P);
if Q = 0 then P = P + 1;
write (P);
Any non-serial interleaving of T₁ and T₂ for concurrent execution leads to