Consider A Database Organized In The Form Of A Rooted Tree. Suppose That We Insert A Dummy Vertex Between Each Pair Of Vertices. Show That, If We Follow The Tree Protocol On The New Tree, We Get Better Concurrency Than If We Follow The Tree Protocol On The Original Tree?

Most Implementations Of Database Systems Use Strict Two-phase Locking. Suggest Three Reasons For The Popularity Of This Protocol?

What Benefit Does Rigorous Two-phase Locking Provide? How Does It Compare With Other Forms Of Two-phase Locking?

What Benefit Does Strict Two-phase Locking Provide? What Disadvantages Result?

What Is A Cascadeless Schedule?why Is Cascadelessness Of Schedules Desirable? Are There Any Circumstances Under Which It Would Be Desirable To Allow Noncascadeless Schedules?

What Is A Recoverable Schedule? Why Is Recoverability Of Schedules Desirable? Are There Any Circumstances Under Which It Would Be Desirable To Allow Nonrecoverable Schedules?

Since Every Conflict-serializable Schedule Is View Serializable, Why Do We Emphasize Conflict Serializability Rather Than View Serializability?

Explain The Distinction Between The Terms Serial Schedule And Serializable Schedule.

Justify The Following Statement: Concurrent Execution Of Transactions Is More Important When Data Must Be Fetched From (slow) Disk Or When Transactions Are Long, And Is Less Important When Data Is In Memory And Transactions Are Very Short.

During Its Execution, A Transaction Passes Through Several States, Until It Finally Commits Or Aborts. List All Possible Sequences Of States Through Which A Transaction May Pass. Explain Why Each State Transition May Occur.