Which of the following describes a database system?
A collection of stored operational data used by the application system of some particular enterprise
A shared collection of logically related data (and a description of this data) designed to meet the information needs of an organisation
A collection of stored data organised in such a way that all user requirements are satisfied by the database. In general there is only one copy of each item of data although there may be controlled repetition of some data.
All of the above
The following shows the development of database systems, but in the wrong order chronologically. Which item should appear last?
Allowing simultaneous access to data using a piece of software called a Database Management System
Storing data on a separate computer file for each application
Storing data so that applications could share some of the same files
Storing data on paper files in a filing cabinet
A relational database system is based on the concept(s) of:
A network of data records
Nested tables
Tables, rows and columns
A tree-like structure of data
All of the above
Oracle was the first commercial relational DBMS. True or false?
True
False
Which of the above definitions relate to the term database?
Numerical, character or other facts which can be recorded in a form suitable for processing by a computer.
The software which is used to control the data and consists of a number of components providing facilities for querying data, data security, integrity and the ability to access the data simultaneously by different uses.
A collection of related data
A description of the data in a database
Which of the following describes the job of a database administrator?
Development, implementation operation of the physical database
Creation of the system catalog
Optimising database performance
Monitoring and controlling database security and authorization: Setting up controls to ensure the quality and integrity of data
Instigating backup and recovery procedures
All of the above
Which is not the function of a DBMS?
A DBMS allows users to create database definitions and to insert, update, delete and query data in the database , using DDL and DML statements respectively
Buffer management - this function is responsible for transferring data to and from main memory and secondary storage
Query processing and optimisation - query processing transforms queries into low-level instructions which are then optimised
Concurrency control – this allows shared access to the database, with multiple transactions being executed at the same time and scheduled in a safe manner.
Recovery - the DBMS must take steps to ensure that if the database fails, it remains in a consistent state.
Keeping track of the physical location of the data in the database in secondary storage
Security and integrity control - the DBMS should prevent unauthorised access the database and include the facility for enforcing integrity constraints whenever a change is made to the database to ensure the data is consistent and correct.
System Catalog – a DBMS includes a repository for storing metadata (data about the data)
One of the following describes logical data independence; the other physical data independence. Which is logical data independence?
With this type of database independence, the conceptual schema shields users from changes to the physical schema. The specification of the physical structure is stored separately and is independent of the application programs that use the data.
With this type of database independence, users are shielded from changes to the conceptual schema (the global view of the data). It is therefore possible to alter the conceptual schema without affecting user views.
There are a number of activities involved in database development. Generally the activity of Database Design will take place before the activity Process Design. True or false?
True
False
Prototyping involves the design of programs that use and process the data in the database. True or false?