Account 4 Marks Question

Tuple refers to a row in a table that represents a set or collection of related data values. It corresponds to the relationship which represents entity type as a set of tuples, where each tuple is an ordered list of values corresponding to attributes of relation. As each tuple represents a distinct data record entity, so no two tuples in a relation (i.e. a table) can have the same combination of values for all their data items. Moreover, if a new tuple is added in the relation, then it should not reflect the existing data-values, otherwise, it will violate the uniqueness constraint and the relation as a whole will not have a minimal super-key.

Whenever entities from different entity types are related to one another in a particular manner, they constitute a relationship type. The relationship prepared by between the two entity types vouchers and employees associates each voucher with the employee who prepared it. Similarly, the relationship authorised by between the two entity types vouchers and employees associates each voucher with the employee who authorises it. Each relationship instance of prepared by (short named as PrepBy) associates one voucher entity with one employee entity. In ER diagrams, relationship types are displayed as diamond shaped boxes, connected by straight lines to the rectangular boxes, which represent the participating entity types.

Data processing is a process of collecting, storing, summarising, analysing and interpreting the data and facts so as to represent reliable information for efficient and effective decision making. Data processing, in short, is a transformation of raw data into useful information. Computer system plays a very important role in processing the accounting data. Data processing requires a mechanism to store data content in a manner that allows easy and convenient retrieval of data as and when required. This can be easily done with the help of computers by designing suitable database for accounting. Moreover, computers also help in eliminating the duplication of data. Unlike the manual accounting system, computers are not subject to tiredness, boredom or fatigue, therefore; the reliability of data processed by computers is very high. Besides reliability, computers can process data at comparatively higher speed and with great degree of precision and accuracy.

Database Normalisation refers to the process of organising and maintaining the data into the database in an efficient manner. The basic rationales behind normalising the database are:

1. To eliminate the data redundancy i.e. to avoid/ eliminate the storage of the same data at more than one places.
2. To ensure data dependency i.e. to store the related data in the database.

Database Normalisation is a very important process as it makes the database free from storage of irrelevant data and removes the duplicate data items from the database. As a result, normalisation ensures more free space available in the database. In addition, normalisation also enhances the reliability and consistency of the database by protecting the database against the data anomalies such as logical and structural problems.