Dbms Function

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1. While users were updating the Premiere Products database, one of the transactions was interrupted. You need to explain to management what steps the DBMS will take to correct the database. Using the sample log in Figure 7-1 1, list and describe the updates that the DBMS will roll back if transaction 2 is interrupted at 8:10. In transaction 2, the DBMS started it at 8:01, added an Orders table record at 8:02, and added an Order Line table record at8:05 and added an Order Line table record at 8:09. To roll back the transaction, the DBMS deletes the three added records. 2. Occasionally, users at Premiere Products obtain incorrect results when they run queries that include built-in (aggregate, summary, or statistical) functions. The DBA…show more content…
b) The DBMSreduces the first customer’s $900 balance to $700 for Elena’s transaction. c) The DBMS read the second customer’s $750balance for Pat’s transaction. d) The DBMS increases the third customer’s $500 balance to $700 for Elena’s transactions) The DBMS reads the third customer’s $700 balance for Pat’s transaction. f) The DBMS calculates the total balance from Steps a, c, and e and displays the total customer balance of $2,350 for Pat the displayed total is $200 higher than the actual total. 3. You’ve explained replication to management, and some managers ask y out for examples of when replication. Could be useful to them. Describe two situations, other than the ones given in the text, when replication would be useful to an organization. Replication could be useful for schools in which remote sites are used to update student information. Also, to keep track of menu items in a chain restaurant business, updated from the various locations. 4. The staff of the marketing department at Premiere Products is scheduled to receive some statistical databases, and they need you to explain these databases to them. (A statistical database is a database that is intended to supply only statistical information to users; a census database is an example of a statistical database.) Using statistical database, users should not be able to
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