INF3703 Combined Questions INF3703.

True & False The objective of SOL performance tuning on the client side is to generate an SOL query that returns the correct answer in the least amount of time, using the maximum amount of resources on the server side All database transactions must display at least the properties of Atomicity, consistency, convenience, and isolation Database recovery techniques are based on the isolation transaction property which indicate that the data used during execution of a transaction cannot be used by a second transaction until the first one is completed Database recovery techniques are based on the durability transaction property. Which ensures that once transaction (committed), they cannot be undone or lost changes are done In a distributed database, concurrency control becomes important because multi-site and multiple-process operations are more likely to create data inconsistencies and deadlocked transactions than single-site systems Open Database Connectivity (ODBC) is a Microsoft middleware that adds objectoriented functionality for access to relational and non-relational Replication transparency, hardware Independence, partition processing; and transaction processing are example of C J. DATE'S twelve commandments for distributed databases All transaction management commands are processed during the parsing and execution phases of query processing Data replication and partitioning is a star schema performance Improvement technique that splits and makes copy of a database table Platform as a Service (PaaS) is the cloud service provider that offers consumers the ability to provision their own resources on demand Data mining is a small, Single-subject data warehouse subsect that provides decision support to a small group of people Fragmentation transparency is the highest level of transparency where the end user or programmer does not need to know that a database is partitioned DBMS and end users interact through the use of systems to generate Information in different sequence Replication transparency, hardware Independence, partition processing; and transaction processing are example of C J. DATE'S twelve commandments for distributed databases The implementation phase of database design includes Installing the DBMS, creating the database storage structure, introduce changes and loading the database. The Data Administrator (DA) and Database Administrator (DBA) functions overlap The level of transparency supported by the DDBMS differs from system to system; location and local mapping are examples of distributed transparency. Attribute hierarchy is a component of star schemas that provide top-down data organization The first stage of logical database design is to translate the physical database design into a set of relational database structure SQL transactions are formed by several SQL statements and database requests. Each database request originates one 1/0 database operation SQL performance tuning is a set of activities and procedures designed to ensure that end-users query is processed by the DBMS in the minimum amount of time, while making best use of resources Working with data in data file is much faster than working with data caches because the DBMS does not have to wait for the hard disk to retrieve the data and no I/O operations are needed to work within the data file Query parsing is a phase in which all rows that match the specified condition(s) are retrieved, sorted and grouped Non-volatile ensures that data are never deleted and new data are continually added, so the warehouse is always growing Distributed DBMS (DDBMS) governs the storage and processing of logically related data over interconnected computer systems It also ensures standard commun1cat1on protocols at the database level The reason behind the development of star schema was because the existing relational modelling techniques such as ER and normalization did not yield a database structure that served advanced data analysis requirements well The data cache is where the data read from the database data files are stored before the data have been read or after the data are written to the database data file Cloud computing allows organisations to quickly and economically add information technology services such as applications, storage, servers, processing power, database and Infrastructure to its IT Portfolio Assignement 1 1 In which phase of the system development life circle are problems examined in greater detail? [1] Planning phase [2] Analysis phase [3] Detail systems design phase [4] Implementation 2 2 A transaction property that guarantees that committed transaction changes cannot be undone or lost, is ___. [1] durability [2] isolation [3] atomicity [4] consistency 1 3 A (an) _____ is reached when all changes to the database are permanently recorded? [1] update statement [2] delete statement [3] commit statement [4] rollback statement 3 4 What happens when a rollback is issued before the termination of a transaction? [1] The DBMS will only store the database for the transaction. [2] The DBMS will restore the database only for that particular transaction. [3] The DBMS will store the database for all the transactions. [4] The DBMS will restore the database for all the transactions. 2 5 The concurrency control problem of lost update occurs when _______. [1] two transactions are executed concurrently and the first one is rolled back after the second transaction has already accessed the data of the first transaction [2] a transaction accesses data before and after one or more other transactions finished working with such data [3] two concurrent transactions are updating the same data element and one of the updates is overwritten by the other transaction [4] transactions executed simultaneously in a multiuser database yield the same result 3 6 A process that ensures a database is immediately updated by operations during the transaction’s execution before the transaction reaches its commit point is called _____. [1] deferred buffer technique [2] write through technique [3] deferred write technique [4] write buffer technique 2 7 ____ occurs when you keep the same number of systems, but migrate each system to a larger system. [1] Scaling up [2] Clustering out [3] Scaling out [4] Clustering up and out 1 8 The characteristic of big data that refers to the changes in the meaning of data based on context, is known as _____. [1] velocity [2] variety 2 [3] volume [4] variability 9 A big data implementation technology designed specifically to distribute and process enormous amounts of data across vast clusters of services is known as _____. [1] visualization [2] Hadoop [3] Cloudera [4] Hortonworks 2 10 High volume, write-once, read-many, streaming access and fault tolerance are key assumptions of the ______ approach to distributed data. [1] reduced file system [2] MapReduce file system [3] Hadoop distributed file system [4] polyglot file system 3 11 Most BI vendors are dropping the term “data mining” and replacing it with the term ______. [1] predictive analytics [2] explanatory analytics [3] data analytics [4] knowledge acquisition 1 12 The end-users decide what techniques to apply to the data when using the ______ mode of data mining. [1] guided [2] prognosis [3] directed [4] automated 1 13 _______ is a collection of technologies used to access any type of data source and manage the data through a common interface. [1] DAO [2] ODBC [3] OLE-DB [4] UDA 4 14 In the ADO.NET framework, the _____ object is the in-memory representation of the data in the database. [1] DataCommand [2] DataReader [3] DataAdapter [4] Dataset 4 15 Which of the following is a reason why a DBMS’s daily operations must be clearly documented? [1] Documentation of daily operations helps a company set its long-term goals. [2] Documentation of the daily operations helps manage the manual data resources of a company. [3] Documentation of the daily operations helps pinpoint causes and solutions of database problems. [4] Documentation of the daily operations helps free the DBA from many lowerlevel technology-oriented tasks. 3 16 _____ deals with ensuring that data is protected against unauthorized access, and if the data is accessed by an authorized user, that the data is used only for an authorized purpose. [1] Integrating [2] Compliance [3] Availability [4] Confidentiality 4 17 The _____ component of a CASE tool produces the information system’s input/output formats. [1] analysis [2] graphics [3] program document generator