For the following exercises, you will address problems and answer questions from the Solmaris Condominium Group staff. You do not use the Solmaris database for any of these exercises.
1. The log shown in Figure 7-19 includes four transactions that completed successfully. For each of the four transactions, list the transaction ID and the table(s) modified. Also, list whether the modification to the table added, changed, or deleted a record.

Figure 7-19

2. Suppose a catastrophe destroys the database just after 10:10. Which transactions in the sample log shown in Figure 7-19 would the recovery program use to update the restored database? Which transactions would have  to be entered again by users?
3. If two of the four transactions shown in Figure 7-19 started at different times, deadlock could have occurred.  Adjust the log to create deadlock between these two transactions.
4. Two of the five tables in the Solmaris Condominium database are defined as follows:

Owner (OwnerNum, LastName, FirstName, Address, City,
State, PostalCode)
CondoUnit (CondoID, LocationNum, UnitNum, SqrFt,
Bdrms, Baths, CondoFee, OwnerNum)

Suppose that a user accesses the database via the following view:
CREATE VIEW OwnerCondo AS
SELECT Owner.OwnerNum, LastName, FirstName, CondoID
FROM Owner, CondoUnit
WHERE Owner.OwnerNum¼CondoUnit.OwnerNum

Suppose further that the database requirements have changed so that a condo can have multiple people as owners, just as people can own more than one condo. What€™s the new database design for the Owner and CondoUnit tables, as well as any other table(s) needed to satisfy the new requirements? Does the new database design affect the OwnerCondo view? If so, write the new defining query for the view.
5. Solmaris Condominium Group currently uses a PC-based DBMS. What factors should they consider in determining how often to back up their database? The factors you include should be specific to Solmaris Condominium Group.

Transcribed Image Text:

Record Updated Before Image After Image Transaction ID Time Action Start 10:00 10:01 Start Insert ServiceRequest (14) (new values) 10:02 Start 10:03 Update Location (2) (old values) (new values) 10:04 Owner (FE182) Update (new values) 3 10:05 (old values) Commit 10:06 Start 10:07 CondoUnit (5) (new values) Update 3 10:08 (old values) Commit 3 10:09 Update (old values) 10:10 CondoUnit (5) (new values) Commit 10:11 Update 10:12 (old values) (new values) 4 CondoUnit (5) Update Owner (FE182) (old values) 4 10:13 (new values) 10:14 Commit