What flat-file data management problems are solved as a result of using the database concept?

In order to continue enjoying our site, we ask that you confirm your identity as a human. Thank you very much for your cooperation.

Get the answer to your homework problem.

Try Numerade free for 7 days

We don’t have your requested question, but here is a suggested video that might help.

What is the number one problem in data warehousing?

Polytechnic University of the Philippines Sta. Mesa, Manila College of Accountancy and Finance Accounting Information S

Views 1,158 Downloads 108 File size 83KB

Report DMCA / Copyright

DOWNLOAD FILE

Recommend Stories

Polytechnic University of the Philippines Sta. Mesa, Manila College of Accountancy and Finance Accounting Information System ACCO 20153 REVIEW AND DISCUSSION QUESTIONS CHAPTER NINE Submitted by: Group 1 Baylon, Billy Joel T. Dialino, Daniel I. Roque, Josh Mikhel G. Semeniano, Ivy Claire B. BSA 2-13 Submitted to: Prof. Froilan A. Magpantay July 05,2020 Review Questions 1. Give five general duties of the database administrator. The five general duties of database administrator are database planning, designing of database, implementation, operation and maintenance, change and growth. 2. What are the four primary elements of the database environment? The four primary elements of the database environment are users, DBMS, DBMS administrator, and Physical database. 3. How are the network and hierarchical models different? In network model, the data modeled as more than one parent per the child. It has concept of multi-parent and it is based on a simple network and the interaction of record types can be represented as links. This model is a many to many relationships b/t object. This is also a complex design and difficult to delete parent record. While hierarchical models, data can be organized in the form of tree structure and contains one parent and many children. It contains the data segments as a relationship of parent and child. This indicates the repetition of the data through a child segment. The data can be represented as a series of records and which are attached with set of field values. It is a parent to child relationship is 1 to Many. This model is easy to design, easy to add and delete records and its relationship b/t models is one to many 4. What flat-file data management problems are solved as a result of using the database concept? The data management problems that are solved as a result of using the database concept are data redundancy, data inconsistency, lack of data independence, data lacks integrity, lack of flexibility and the inability to share data. 5. What are four ways in which database management systems provide a controlled environment to manage user access and the data resources? The four ways in which database management systems provide are the program development, backup and recovery, database usage reporting, and database access. 6. Explain the relationship between the three levels of the data definition language. As a user, which level would you be most interested in? One of the relations between the three views the internal views, the conceptual view and the user view is the arrangement of data and its physical appearance for the programmer, and the logical arrangement of the data for the programmer, and the view of the data for the user. Each of the views represents a particular arrangement of data. Users are basically interested in the user view because it is comfortable for the user to retrieve the data from this level. 7. What is a primary key? It is the unique key which is used to identify each record in the table. 8. What is a foreign key? It is the primary key which is present in another table and it is used to determines the relationship between two tables. 9. What is a data dictionary, and what purpose does it serve? Data dictionary is a collection of data objects descriptions or descriptions of items that are present in the data model which benefits the programmers for reference. 10.Give an application for a partitioned database. Partitioned data bases will be of use in retail chains FMCG goods because these stores are located at different places they can store the data in individual locations. 11.What is an entity? Entity is an object that contains the information about the objectives of the database management system. 12.Give an application for a replicated database. An organization involving in distribution of products to the local markets having various distribution locations can be an example of an organization using a replicated database. The reason for this being the distribution company with multiple locations needs data at all times. 13.Discuss and give an example of the following types of associations: (1:0,1), (1:1), (1:M), and (M:M). 1:0, 1 Relationship – in this relationship, the table can contain zero or one type of record on the other table in the relationship. For example, when a car is given to only the general manager of the organization and the others are not given then it shows a 1:1 relation.  1:1 Relationship – one to one relationship means any two tables should contain one record at any side of the relationship. For example, student_id is given only to one particular student. That means no other should have the same student_id.  1:M Relationship – one-to-many relationships shows that one record in the table can maintain relationships with more than one record in other table but not vice versa. For example, if the organizations offer a bus facility for travelling from the railway station to the company premises and if there are many employees sharing that facility then it shows a 1:M facility.  Many to Many Relationships - in many to many relationships both the tables should have access to more than one record. For example, if the organization is providing transport facility from a number of points to the company premises by a number of buses and if there are many people sharing that transport then it is called as an M:M relationship. 14. Distinguish between association and cardinality. The term association pertains to the nature of the relationship between two entities. This is represented by a verb such as shipped, requests, or receives. Cardinality is the degree of association between two entities. 15. Explain how a separate linking table works in a many-to-many association. For each occurrence of record types X and Y, zero, one, or many occurrences exist of record type Y and X, respectively. An example would be a student-professor relationship. Each student has multiple professors each semester, and each professor has multiple students each semester. 16. What are the four characteristics of properly designed relational database tables? 1.All attribute values in any column must be of the same class. 2. Each column in a given table must be uniquely named. 3. Tables must conform to the rules of normalization. [ free from structural dependencies including repeating groups, partial dependencies, and transitive dependencies] 4. The value of at least one attribute in each occurrence (row) must be unique. This attribute is the primary key. The values of the other (non-key) attributes in the row need not be unique. 17. What do the relational features restrict, project, and join mean? 1)Restrict—Extracts specified rows from a specified table. 2) Project—Extracts specified attributes (columns) from a table to create a virtual table. 3) Join—Builds a new physical table from two tables consisting of all concatenated pairs of rows, one from each table 18. What are the conditions for third normal form (3NF)? A relation is in third normal form, if there is no transitive dependency for non-prime attributes as well as it is in second normal form. A relation is in 3NF if at least one of the following condition holds in every non-trivial function dependency X –> Y: X is a super key. 19. Explain how the SELECT and WHERE commands help a user to view the necessary data from multiple database files (tables). The SQL SELECT statement returns a result set of records from one or more tables. A SELECT statement retrieves zero or more rows from one or more database tables or database views. In most applications, SELECT is the most commonly used data manipulation language (DML) command. The SQL WHERE clause is used to specify a condition while fetching the data from a single table or by joining with multiple tables. If the given condition is satisfied, then only it returns a specific value from the table. You should use the WHERE clause to filter the records and fetching only the necessary records. 20. What is a data model? A data model refers to the logical inter-relationships and data flow between different data elements involved in the information world. It also documents the way data is stored and retrieved. Data models facilitate communication business and technical development by accurately representing the requirements of the information system and by designing the responses needed for those requirements. Data models help represent what data is required and what format is to be used for different business processes 21. How can a poorly designed database result in unintentional loss of critical records? The deletion anomaly may cause records to be deleted unintentionally and may occur for some time before the problem is noticed. A deletion anomaly occurs when an item in one file is legitimately deleted. The problem occurs when this file is linked to another file, which may also have a record deleted, due to its link. If the second record should not be deleted, then an update anomaly has occurred. 22. What is a user view? A user view is the set of data that a particular user sees. Examples of user views are computer screens for entering or viewing data, management reports, or source documents, such as an invoice. 23. Does a user view always require multiple tables to support it? Explain. User view derives from underlying database tables. Simple views maybe constructed from a single table, while more complex views may require several tables. 24. What two conditions must valid entities meet? Following are the conditions should be met before an entity is referred as a weak entity: The entity should be “existence-dependent” on its parent entity. If an entity is referred as an “existence-dependent”, then that entity can exist in the database if and only if when it is related with another entity existence. 25. Can two different entities have the same defining attributes? Explain. Because attributes are logical and relevant characteristic of an entity, they are unique to it. Therefore, the same attributes should not be used to define two different entities. Discussion Questions 1. In the flat-file data management environment, users are said to own their data files. What is meant by the ownership concept? The flat-file environment promotes a single-user view approach to data management whereby end users use their own data files rather than share them. Data files are therefore structured, formatted, and arranged to suit the specific needs of the owner as the primary user of the data. 2. Discuss the potential aggravations you might face as a student as a result of your university using a flat-file data management environment, that is, different files for the registrar, library, parking, and so on. If I were to use a flat-file data system, many more forms would have to be filed out. A flatfile system would create more paperwork for everyone and be difficult to keep students files up to date. Without up to date files, it would create delays in grades, graduation and solving issues that arise. 3. Discuss why control procedures over access to the data resource become more crucial under the database approach than in the flat-file environment. What role does the DBMS play in helping to control the database environment? Under the database concept, the data is centrally stored with many different users accessing the database. However, each user should not have access to the whole database. Under the flat-file data management environment where the data and programs were linked, the user access problem was not as great a threat. The DBMS is a special software system that is programmed to know which data each user is authorized to access. This controlled authorization is crucial in centrally stored DBMSs. 4. What is the relationship between a database table and a user view? Database table is basically the digital or physical representation of the table whereas the view may require inputs from several databases. User views are the end users may see the physical representation of the database. A table consist data while a view is a select statement and which can be stored in database. 5. Explain how linkages between relational tables are accomplished. Linkages in database of relational database can be achieved by defining certain algebraic functions like the restrict function, the project function, and the join function. These functions help the programmer to achieve a link between relational database tables. 6. Explain the purpose of an ER diagram in database design. One of the main purposes is to build a database which can be efficiently made and easy to be handled. The entity relationship help in easy maintenance of the database. 7. SQL has been said to place power in the hands of the user. What does this statement mean? The statement “power in hand of user” signifies SQL is aimed to bring power to the end users. It is aimed to give the end user plenty of advantage in terms of creating user friendly interfaces which do not require much of technical knowledge, easy navigation, easy to understand, easy to use, and easy to prepare reports in case of requirement. 8. Discuss the importance of the role of the database administrator. In the flatfile environment, why is such a role not necessary? What tasks does the DBA perform? The database administrator plays an important role by receiving data request from users which the DBA analyzes and wherever there is a need for additional database permissions will be granted. In a flat-file environment the importance for data base administration as flat files are more or less maintained by individuals and often the information is related to a particular task is stored in flat files because these files are more or less stand alone data bases they will not be requiring the services of a data base administrator. The database administrator performs various tasks such as database planning, database design, database implementation, and database change and growth. 9. As users determine new computer application needs, requests must be sent to both the system programmers and the DBA. Why is it important that these two groups perform separate functions, and what are these functions?  Requests need to be sent to both the programmers and database administrators because the database administrator will be deciding whether the user needs to be given access to new computer application as requested by the user, if the request is genuine then the DBA grants permission.  The functions of DBA are DBA needs to perform administrative functions, needs to perform the functions of a communicator, needs to perform the functions of a manager. While the functions of a programmer are a programmer needs to perform the role of a developer by creating new software programs, acts as a problem solver by identifying errors in the programs and by correcting them, acts as a maintenance engineer by looking after the systems administrations and maintenance tasks. 10.Why is a separate link table required when an M:M association exits between related tables? Separate link table is required for the creation of M:M association. This is because foreign key cannot be embedded in the either table. 11. As an accountant, why would you need to be familiar with data normalization techniques? Database normalization is a technical matter that is usually the responsibility of systems professionals. However, the subject has implications for internal control that make it the concern of auditors also. For example, the update anomaly can generate conflicting and obsolete data values; the insertion anomaly can result in unrecorded transactions and incomplete audit trails; and the deletion anomaly can cause the loss of accounting records and the destruction of audit trails. Although most auditors will never be responsible for normalizing an organization's databases, they should have an understanding of the process and be able to determine whether a table is properly normalized. 12. How does a database lockout contribute to financial data integrity? A database lockout prevents multiple users from accessing the same table simultaneously and making changes to data values while they are temporarily inconsistent. Lockouts force changes to be made sequentially to ensure data accuracy. 13. How does concurrency control contribute to financial data integrity? Database concurrency controls ensure the completeness and accuracy of a distributed database at remote sites where the same beginning data balances are updated by different transactions. 14. In a relational database environment, certain accounting records (for example, journals, subsidiary ledgers, and event general ledger accounts) may not exist. How is this possible? Database accounting systems are transaction-based rather than account-based. The focus is on capturing important details of transactions that may be lost when they are forced into the structure of traditional accounting records. The transaction tables are then to be used to reconstruct traditional accounting records, such as Accounts Receivable and Accounts Payable. 15. Explain how to link tables in a 1:1 association. Why may this be different in a 1:0,1 associations?  For every occurrence in record type X, either zero or one occurrence exists of record type Y. An example would be that, for every student, only one social security number exists.  For every occurrence in record type X, zero, one, or many occurrences exist of record type Y. An example would be buyers of assigned seating at concerts. Each potential buyer would leave the sales box office with zero, one, or many seats. 16. Discuss the accounting implications of the update, insertion, and deletion anomalies associated with Improperly normalized tables. The insertion and update anomalies would create record keeping and operational problems for the firm. However, flawed databases design that prevents the insertion of records, or requires the user to perform excessive updates, would attract attention quickly. The presence of the deletion anomaly is less conspicuous, but potentially more serious from an accounting perspective. Because the deletion anomaly may go undetected, the user may be unaware of the loss of important data until it is too late. This anomaly can result in the unintentional loss of critical accounting records and the destruction of the audit trail. 17. Give three examples that illustrate how cardinality reflects an organization’s underlying business rules. 1. Purchases the same items from many suppliers M:M 2. Purchases all items from a certain supplier 1:M 3. 1:M or 1:1 18. Discuss the key factors to consider in determining how to partition a corporate database. The partitioned approach works best for organizations that require minimal data sharing among users at remote sites. To the extent that remote users share common data, the problems associated with the centralized approach will apply. The primary user must now manage requests for data from other sites. Selecting the optimum host location for the partitions to minimize data access problems requires an in-depth analysis of end-user data needs. 19. Distinguish between a database lockout and a deadlock. Database deadlock is a condition in which no data can be accessed as sites are held at halt due to locks created by many users for long time. Database lockout is a controlling method inbuilt within database software to ensure data consistency and accuracy while recording transactions. 20. Replicated databases create considerable data redundancy, which is in conflict with the database concept. Explain the justification of this approach.

The primary justification for a replicated database is to support read-only queries in situations involving a high degree of data sharing, but no primary user exists. With data replicated at every site, data access for query purposes is ensured, and lockouts and delays due to network traffic are minimized. A potential problem arises, however, when replicated databases need to be updated by transactions. Since each site processes only local transactions, the common data attributes that are replicated at each site will be updated by different transactions and thus, at any point in time, will have uniquely different values. System designers need to employ currency control techniques to ensure that transactions processed at different locations are accurately reflected in all the databases copies.