Transaction (Locking Protocols) Transaction 1 wants to: R1X) W10X) R1(Y) W1Y) W1X) Transaction 2 wants to:...
2. Given the following three transactions T1 = r1(x); w1(y); T2 = r2(z); r2(y); w2(y); w2(x); T3 = r3(z); w3(x); r3(y); Consider the schedule S = r1(x); r3(z); r2(z); w3(x); r2(y); r3(y); w2(y); w1(y); w2(x); a. Draw the precedence graph of schedule S, and label each edge with data item(s). b. Based on the precedence graph, determine whether S is conflict serializable and justify your answer. If it is serializable, specify all possible equivalent serial schedule(s).
Consider the following transaction schedule: r1(X), r2(X), r3(X), r1(Y), w2(Z), r3(Y), w3(Z), w1(Y) This schedule is conflict-equivalent to some or all serial schedules. Determine which serial schedules it is conflict-equivalent to, and then identify a true statement from the list below. Select one: a. The schedule is conflict-equivalent to (T3, T1, T2) b. The schedule is not serial c. The schedule is conflict-equivalent to (T3, T2, T1) d. The schedule is conflict-equivalent to (T2, T3, T1) e. The schedule is...
Consider the following order of operation requests from transactions T1. T2. T3 r1 (A) r2 (A) r3 (A) r1 (B) r2 (B) w1 (B) w2 (A) Show the resulting schedule table when we have a scheduler that supports shared exclusive, and update locks.
Question 5. (20pts) (Briefly justify your answer) 1) Consider three transactions: T1, T2 and T3. Draw the precedence graph for the following schedule consisting of these three transactions and determine whether it is conflict serializable a) (5points) S: R1(X); R3(Z); W2(X); RI(Z); R3(Y); W2(Y), R3(Z), W1(Z), b) (5points) S: RI(X); R3(Z); W20x); RI(Y); R2(Y); W3(Y); R3(Z); WI(Z);
1. What is the difference between Two-Phase Locking (2PL) and Strict Two-Phase Locking? What condition to Strict 2PL prevent that 2PL does not prevent? 2. What are deadlocks? What are two techniques for detecting and resolving deadlocks? 3. In the figure below, R(X, y) means read database item X into variable y and W(X, y) means write variable y into database item y. Column T1 shows transaction T1's operations and column T2 shows T2's operations. Columns Aand_B show the values...
1) Explain two-phase locking. 2) Explain the meaning of the expression of ACID transaction.
please explain all rhanks Search 19:24 If the probability that head is 1/2 and the probability that the back is 1/2, coin is repeatedly throws twice w1 (H,H) w2=(T,H) w3 (H,T) w4= (T,T) The sample space is {w1,w2,w3,w4} The random variable X: R and the random variable Y: R for all we, the probability P is and is defined P ((w)) X (w) 0 for we{w1,w3} X(w)=1, for w e (w2, w4} Y (w) 0, for we{w1,w2} Y(w)1, for w{w3,...
Given the following binary relations: The relation Rl on {w, 1, y, z), where R1 = {(w, w), (w, 1), (x, w), (x, 1 ), (x, z), (y, y), (z,y),(2, 2)). The relation R2 on (a, b, c), where R2 = {(a, a ), (b, b), (c, c), (a, b), (a, c), (c, b)}. The relation R3 on {x,y,z}, where R3 = {(1, 2), (9,2), (2, y)}. Determine whether these relations are: (1) reflexive, (2) symmetric, (3) antisymmetric, (4) transitive?
Assume an isoquant for a fixed level of output equal to ¯y = 1/2x 1 2 1 x 1 3 2 Fix w1 = 1. Show how the cost minimizing bundle changes as w2 moves from 1 to 2. You can graph x1 and x2 on separate graphs as a function of w.\
R 014 1)2 = Ovi 1) In this circuit, 11 = 520 A, R1 = 43 12, Zc = -1892, V1 = 14.92-60.2, R2 = 28 , ZL = j2.502, and V2 = 14.92-60.2. Write the mesh equation for Ic. What is the total impedance that is used in this equation? Express this impedance in rectangular form X = a +jb, and enter your answer as the straight sum of the real and imaginary parts a + b. Show 3...