INF3703 Flash Cards.

Chapter 10-13 Flash Cards The mainframe environment enables an OLAP system to be divided into several components that define its architecture. true As long as two transactions, T1 and T2, access ____ data, there is no conflict, and the order of execution is irrelevant to the final outcome. shared common unrelated locked unrelated A characteristic of operational data is ____. summarized data hundreds of gigabytes high normalization historic data high normalization ____ transparency ensures that the system will continue to operate in the event of a node failure. Transaction Distribution Failure Performance Failure A(n) ____ specifically reserves access to the transaction that locked the object. shared lock exclusive lock binary lock deadlock exclusive lock On the client side, the objective is to generate a SQL query that returns the correct answer in the least amount of time, using the minimum amount of resources at the server end. The activities required to achieve that goal are commonly referred to as ____ tuning. client and server database SQL performance DBMS performance SQL performance The implicit beginning of a transaction is _____. 1) when the database is started 2) when a table is accessed for the first time 3) when the first SQL statement is encountered 4) when the COMMIT command is issued when the first SQL statement is encountered The transaction recovery write-ahead-log protocol ensures that transaction logs are always written before any database data are actually updated. True False True ANSI defines four events that signal the end of a transaction. Of the following events, which is defined by ANSI as being equivalent to a COMMIT? 1) Five SQL statements are executed. 2) The end of a program is successfully reached 3) The program is abnormally terminated. 4) The database is shut down for maintenance. The end of a program is successfully reached To work with data, the DBMS must retrieve the data from permanent storage and place it in RAM. 1) True 2) False True When setting optimizer hints, _____ instructs the optimizer to minimize the overall execution time, that is, to minimize the time it takes to return the total number of rows in the query result set. This hint is generally used for batch mode processes. 1) ALL_ROWS 2) FIRST_ROWS 3) INDEX(P_QOH_NDX) 4) OPTIMIZATION_ROWS INDEX(P_QOH_NDX) If there is no index, the DBMS will perform a _____ scan. 1) loop 2) range 3) row ID table access 4) full table full table The _____ cache is used as a temporary storage area for ORDER BY or GROUP BY operations, as well as for index-creation functions. 1) data 2) SQL 3) sort 4) optimizer sort The _____ is a shared, reserved memory area that stores the most recently executed SQL statements or PL/SQL procedures, including triggers and functions. 1) buffer cache 2) procedure cache 3) data cache 4) permanent storage procedure cache Which of the following is the first step of query processing at the DBMS server end? 1) Executing 2) Parsing 3) Fetching 4) Delivering Parsing Character field comparisons are faster than numeric, date, and NULL comparisons. 1) True 2) False False The SQL cache stores the end-user written SQL