Given the following schedule

$```$

T$1$:

read$\_$item$($enrolment$)$

enrolment $=0$

write$\_$item$($enrolment$)$

read$\_$item$($limit$)$

limit $=100$

write$\_$item$($limit$)$

read$\_$item$($remaining$)$

remaining $=$ limit

write$\_$item$($remaining$)$

T$2$:

read$\_$item$($enrolment$)$

enrolment $++$

write$\_$item$($enrolment$)$

read$\_$item$($remaining$)$

remaining $-$

write$\_$item$($remaining$)$

$```$

Show that this schedule is conflict serializable, via a precedence graph. Show that this schedule is view serializable.

Apply the following concurrency control mechanisms:

i$.$ Two$-$phase locking

ii$.$ Timestamping $\backslash ((\backslash$mathrm$\{$TS$\}(\backslash$mathrm$\{$T$\}1)=1,\backslash$mathrm$\{$TS$\}(\backslash$mathrm$\{$T$\}2)=2)\backslash )(40$ points$)$ Given the following schedule:

$```$

T$1$:

read$\_$item$($enrolment$)$

enrolment $=0$

write$\_$item$($enrolment$)$

read$\_$item$($limit$)$

limit $=100$

write$\_$item$($limit$)$

read$\_$item$($remaining$)$

enrolment $++$

write$\_$item$($enrolment$)$

remaining $=$ limit

write$\_$item$($remaining$)$

T$2$:

read$\_$item$($enrolment$)$

read$\_$item$($remaining$)$

remaining $--$

write$\_$item$($remaining$)$

$```$

Apply the following concurrency control mechanisms:

a$.$ Two$-$phase locking

b$.\backslash (\backslash$quad $\backslash )$ Timestamping $\backslash ((\backslash$mathrm$\{$TS$\}(\backslash$mathrm$\{$T$\}1)=1,\backslash$mathrm$\{$TS$\}(\backslash$mathrm$\{$T$\}2)=2)\backslash )$