Let $S$ be the following schedule of operations of three transactions $T_1$, $T_2$ and $T_3$ in a relational database system:
$$R_2(Y), R_1(X), R_3(Z), R_1(Y)W_1(X), R_2(Z), W_2(Y), R_3(X), W_3(Z)$$
Consider the statements $P$ and $Q$ below:
- $P$: $S$ is conflict-serializable.
- $Q$: If $T_3$ commits before $T_1$ finishes, then $S$ is recoverable.
Which one of the following choices is correct?
- Both $P$ and $Q$ are true
- $P$ is true and $Q$ is false
- $P$ is false and $Q$ is true
- Both $P$ and $Q$ are false