Transaction Management Transaction Management

Problem $1.$ Transaction management. $Ri(x)$ refers to transaction $Ti$ reading item $x$ and $Wj(y)$ refers to

transaction Tj writing item y$.$ For each schedule below:

a$)S1$:$R_1(x)R_1(y)R_2(y)R_2(x)W_1(z)W_2(z)W_1(x)W_2(y)$

b$)$ S$2$: $R_1(x)R_2(y)R_2(x)W_2(z)W_1(x)W_1(z)W_2(y)$

$[20+20$ points

Problem $1.$ Transaction management. Ri$($x$)$ refers to transaction Ti reading item x and Wj$($y$)$ refers to transaction Tj writing item y$.$ For each schedule below:

a$)$ S$1$: R$1($x$)$ R$1($y$)$ R$2($y$)$ R$2($x$)$ W$1($z$)$ W$2($z$)$ W$1($x$)$ W$2($y$)$

b$)$ S$2$: R$1($x$)$ R$2($y$)$ R$2($x$)$ W$2($z$)$ W$1($x$)$ W$1($z$)$ W$2($y$)$

$[20+20$ points$]$ Prove whether or not it is conflict serializable

$[10+10$ points$]$ If it is serializable write down an equivalent serial schedule. If it is not serializable explain why not

Problem $2.[20+20$ points$]$ Assuming the $2$PL protocol is in place, prove the presence$/$absence of deadlocks for each one of the previous schedules