Hi Expert, the questions below is under Database Management System and the information is in full. Please help to solve the questions, thanks.
Refer to Figure Q1a for the partial steps for the use case "Order Item". If available..count for selected item > 0 Update selected item available..count Add item to order Figure Qla Several concurrent processes are running "Order Item". Discuss whether the following event can happen. Lost update Deadlock Use an appropriate example/scenario including the interleaving steps if an event can arise or provide a reason if it is not possible for an event to happen. b) The use case "Order Item" is implemented as a stored procedure. Suggest how you can secure the stored procedure e.g., who can execute it. Explain. c) Given the scenarios described by the transaction log in Figure Q1b, explain the database recovery procedure for transactions T1 to 14. Record Painter Transaction ID Reverse Painter Forward Pointer Time Type of Operation Table Row ID Before Image After Image T1 0 1 2 3 1 Suppliecoder 52 52, 7, .. T1 T2 0 3 4 T2 T2 12:01:32 12:01:36 12:01:55 12:02:01 12:02:24 12:04:26 12:05:00 Start Insert Start Insert Update Start Update Ouderltema Item A123,3 7 A123, 3, 7, ... 7. 15, ... 4 7,31,.. 5 6 7 0 TE T3 7 9 Item 7 7, 15, .. 7,3,- Checkpoint 8 2 0 T1 T3 9 Item 10 10, 22, ... 10, 3, ... T4 10 11 12 13 12:05:41 12:06:23 12:35:33 12:35:36 12:36:36 12:37:33 0 10 9 11 52 Rollback Update Start insert Commit Insert 11 13 0 0 Suppliecorder T4 TE T4 52.7. 53 53, 10, SupplierOrder Crash! Figure Q16 Refer to Figure Q1a for the partial steps for the use case "Order Item". If available..count for selected item > 0 Update selected item available..count Add item to order Figure Qla Several concurrent processes are running "Order Item". Discuss whether the following event can happen. Lost update Deadlock Use an appropriate example/scenario including the interleaving steps if an event can arise or provide a reason if it is not possible for an event to happen. b) The use case "Order Item" is implemented as a stored procedure. Suggest how you can secure the stored procedure e.g., who can execute it. Explain. c) Given the scenarios described by the transaction log in Figure Q1b, explain the database recovery procedure for transactions T1 to 14. Record Painter Transaction ID Reverse Painter Forward Pointer Time Type of Operation Table Row ID Before Image After Image T1 0 1 2 3 1 Suppliecoder 52 52, 7, .. T1 T2 0 3 4 T2 T2 12:01:32 12:01:36 12:01:55 12:02:01 12:02:24 12:04:26 12:05:00 Start Insert Start Insert Update Start Update Ouderltema Item A123,3 7 A123, 3, 7, ... 7. 15, ... 4 7,31,.. 5 6 7 0 TE T3 7 9 Item 7 7, 15, .. 7,3,- Checkpoint 8 2 0 T1 T3 9 Item 10 10, 22, ... 10, 3, ... T4 10 11 12 13 12:05:41 12:06:23 12:35:33 12:35:36 12:36:36 12:37:33 0 10 9 11 52 Rollback Update Start insert Commit Insert 11 13 0 0 Suppliecorder T4 TE T4 52.7. 53 53, 10, SupplierOrder Crash! Figure Q16
