Project: Choose one of the following problems to answer. Post your response to this week's discussion forum at least two days before the end of the week. Read all postings and respond to at least two.
Suppose your database system has failed. Describe the database recovery process and the use of deferred-prepare and prepare-through techniques.
Suppose you are asked to evaluate a DBMS in terms of lock granularity and the different locking levels. Create a simple database environment in which these features would be important.
Research the Dining Philosophers problem on the Internet. Summarize what you find and describe how this classic problem relates to deadlock and concurrency control. describe how you could prevent this problem from occurring.
There are several different kinds of locks used with databases. Using your text, the Internet, and any other sources you have available, study the concept of locking. Briefly describe each type of lock that you uncover during your studies, along with its advantages and disadvantages.
prepare or find (online) SQL statements that might be used in transaction management and describe how they work. Here's an ex with the answer:
The following transaction registers the credit sale of a product to a customer. Start transaction
INSERT INTO INVOICE -- Add record to invoice
(INV_NUM, INV_DATE, ACCNUM, TOTAL)
UPDATE INVENTRY -- Update the quantity on hand of the product
SET ON_HAND = ON_HAND - 100
WHERE PROD_CODE = '345TYX';
UPDATE ACCREC -- Update the customer balance account
The above statement have accomplished:
Create the invoice record.
Update the inventory data.
Update the customer account data.
The DBMS will ensure that all SQL statements are executed and completed before committing all work. If, for any reason, one or more of the SQL statements in the transaction cannot be completed, the entire transaction is aborted and the database is rolled back to its previous consistent state.
Project: Make sure that your E-R diagram and your data dictionary are accurate in every detail. (Entities and attributes are the same.)
Use the group E-R diagram and data dictionary from the previous two weeks to develop SQL statements that will create tables.
After your tables are created, enter a minimum of 3 sets of data for each table.
Use the SQL exs from the last two weeks and anything you can find on the Internet as exs on how to prepare the SQL instructions.
Attach your SQL code for creating the tables and adding data to each table to this assignment in a single text document. Post your the ERD and Data Dictionary that you use to generate your code to your file exchange.
Note: The attached pvfc1.txt file used in week 1 is an ex of what you code should look like. Except that your code should include comments for each block of text.
Attachment:- TG14 Assignment.zip