Develops when not all of the required changes in the redundant data are made successfully.

Structural dependence

A file system exhibits structural dependence, which means that access to a file is dependent on its structure. For example, adding a customer date-of-birth field to the CUSTOMER, Given this change, none of the previous programs will work with the new CUSTOMER file structure. Therefore, all of the file system programs must be modified to conform to the new file structure. In short, because the file system application programs are affected by change in the file structure, they exhibit structural dependence. Conversely, structural independence exists when it is possible to make changes in the file structure without affecting the application program’s ability to access the data.

Data dependence:

Even changes in the characteristics of data, such as changing a field from integer to decimal, require changes in all the programs that access the file. Because all data access programs are subject to change when any of the file’s data storage characteristics change (that is, changing the data type), the file system is said to exhibit data dependence.

Conversely, data independence exists when it is possible to make changes in the data storage characteristics without affecting the application program’s ability to access the data.

Data redundancy:

Data redundancy exists when the same data are stored unnecessarily at different places. The file system’s structure makes it difficult to combine data from multiple sources, and its lack of security renders the file system vulnerable to security breaches. The organizational structure promotes the storage of the same basic data in different locations. The different problems with data redundancy are:

Poor data security

Having multiple copies of data increases the chances for a copy of the data to be susceptible to unauthorized access.

Data inconsistency

Data inconsistency exists when different and conflicting versions of the same data appear in different places. For example, suppose you change an agent’s phone number or address in the AGENT file. If you forget to make Corresponding changes in the CUSTOMER file, the files contain different data for the same agent. Reports will yield inconsistent results that depend on which version of the data is used.

Data anomalies

The dictionary defines anomaly as “an abnormality.” Ideally, a field value change should be made in only a single place. Data redundancy, however, fosters an abnormal condition by forcing field value changes in many different locations. A data anomaly develops when not all of the required changes in the redundant data are made successfully.

The data anomalies are commonly defined as follows:

Update anomalies

If agent Leah F. Hahn has a new phone number, that number must be entered in each of the CUSTOMER file records in which Ms. Hahn’s phone number is shown. In this case, only three changes must be made. In a large file system, such a change might occur in hundreds or even thousands of records. Clearly, the potential for data inconsistencies is great.

Insertion anomalies

If only the CUSTOMER file existed, to add a new agent, you would also add a dummy customer data entry to reflect the new agent’s addition. Again, the potential for creating data inconsistencies would be great.

Deletion anomalies

If you delete the customers Amy B. O’Brian, George Williams, and Olette K. Smith, you will also delete John T. Okon’s agent data. Clearly, this is not desirable. 

Find More DBMS Question and Answers

is processed data, that can be used as the foundation for decision making.

The results obtained from using wind speed and atmospheric pressure to predict weather can be termed as _____.

Which of the following is true of Knowledge?

It has its bedrock in information.

_____ is the key to good decision making.

Production of accurate, relevant, and timely information

What is the name for data about data?

_____ is a discipline that focuses on the proper generation, storage, and retrieval of raw facts needed by an information system.

What is a benefit of using a DBMS?

It helps create an environment for end users to have access to more data.

The _____ manages interaction between the end user and the database.

The _____ receives all application requests and translates them into the complex operations required to fulfill requests.

spur-of-the-moment question

Wider access to well-managed data promotes a(n) _____ view of the organization's operations and a clearer view of the big picture.

What is the name for an answer to a query that the DBMS sends back to the application?

A single-user database that runs on a personal computer is called a(n) _____ database.

A database that supports data distributed across several different sites is called a(n) _____ database.

The _____ is a specialized database that stores data in a format optimized for decision support.

Another name for a production database is a _____ database.

John is working in the customer table and needs to know what customers are located in Florida. To find the information he would _____.

A _____ database supports a relatively small number of users or a specific department within the organization.

Which of the following products do not provide an enterprise database?

The design of a _____ database recognizes the use of historical and aggregated data.

Data processing (DP) specialists are in existence because of _____.

The need to track data and produce required reports.

A database that supports data located at a single site is called a _____ database.

_____ refers to the activities that focus on the design of the database structure that will be used to store and manage end-user data.

A _____ is a logically connected set of one or more fields.

All fields for a specific entity can be grouped together as a _____.

A raw fact such as a telephone number is known as _____.

Data _____ exists when it is possible to make changes in the data storage characteristics without affecting the application program's ability to access the data.

Because all data access programs are subject to change when any of a file's data storage characteristics change (that is, changing the data type), a file system is said to exhibit _____.

The human being views data in a _____ format.

_____ independence exists when it is possible to make changes in the file architecture without affecting the application program's ability to access the data.

Data _____ exists when the same data are stored unnecessarily at different places.

Which of the following would result in a data anomaly?

Inconsistent redundant data

Data _____ is defined as "the condition in which all of the data in the database are consistent with the real-world events and conditions."

A data _____ develops when all of the required changes in the redundant data are not made successfully.

The term _____ system refers to an organization of components that define and regulate the collection, storage, management, and use of data within a database environment.

_____ are the people who use application programs to run the organization's daily operations.

Database management systems, operating systems, applications and utilities are all examples of _____.

_____ are considered database architects.

Where does the DBMS store the definitions of data elements and their relationships?

_____ are the instructions and rules that govern the design and use of the database system.

Activities that make the database perform more efficiently in terms of storage and access speed are known as performance _____.

The DBMS allows the user to specify what must be done, without having to specify how it is to be done, by using a(n) _____.

_____ deals with fixing the database after a failure such as a disk or power failure.

_____ is the de facto query language and data access standard supported by the majority of DBMS vendors.

An example of a general-purpose database would be _____.

ProQuest databases that contain newspaper articles for a variety of topics.

A(n) _____ database focuses primarily on storing historical data and business metrics used exclusively for tactical or strategic decision making.

Which of the following DBMS functions relieves users from defining and programming the physical data characteristics?

_____ ensure that the database is functioning properly.

Which of the following can occur if when changes are made to a database where different versions of the same data are stored in different places?

What is a problem with redundant information?

Is data about data through which the end

Which of the following is used to generate information required to make tactical or strategic decisions?