Assessment 1 Design Databases

Part A: Designing the Database

1.

Organisational and task Requirements

Scope

The first task in database design is to determine the database functionality. It will need to meet with the client in order to determine what the database needs to do.

Data redundancy is the word for repeating data in the same data system. It should be minimized because it is not efficient for the company. It takes a lot of space in the database and is wasting space that could be used for something else.

There are many types of queries. These are 2 queries that I have chosen to look at:

Crosstab queries

Crosstab queries are used to calculate and restructure data so that readers have an easier time of analysing the data.

Update queries

Update query makes changes to a whole table or group of tables.

Forms are the final product of your data. It should look presentable and easy to understand. A form will make the information look professional and makes the data unique. With the forms, all data would look the same in every table, every database in every company. Forms will create varieties in designs.

Reports will be based on the data that has been entered. It is going to summarise the data entry and make the data easy to identify. Reports of the database act as a summary and make the information easier to collect. Open data and go to design tab, add a group and click sort.

Testing the database is important to provide a database that is efficient and effective for a company. It should follow the guidelines of ACID (atomic, consistent, isolated and durable). The testing can be done by any one that will use or has knowledge of databases. Users will be dealing the most with the database and can help give opinions about the database. Sample data has to be easy to use and visual representation.

2.

The steps to developing a logical data model are:

1.Specify the primary keys.

2.Finds the attributes for the entities

3.Normalizing

3.

Microsoft AccessI would use Microsoft Access as a database system. This system is very cheap and very easy to use. For people that are new to database systems, Microsoft Access is a great way to create databases that are easy to read and understand. Access is also very simple to use with basic features for all database needs. It is one of the most common database systems with all the features a database will need. This includes visual presentations and graphs.

Part B: Developing the database

1.

After you create a field and set its data type, you can set additional field properties. The field’s data type determines which other properties you can set. For example, you can control the size of a Text field by setting its Field Size property.

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 Field Size property.

For Number and Currency fields, the Field Size property is particularly important, because it determines the range of field values. For example, a one-bit Number field can store only integers ranging from 0 to 255.

The Field Size property also determines how much disk space each Number field value requires. Depending on the field size, the number can take up exactly 1, 2, 4, 8, 12, or 16 bytes.

NOTE   Text and Memo fields have variable field value sizes. For these data types, Field Size sets the maximum space available for any one value.

2.

There are many types of queries. These are 2 queries that I have chosen to look at:

Crosstab queries

Crosstab queries are used to calculate and restructure data so that readers have an easier time of analysing the data.

Update queries

Update query makes changes to a whole table or group of tables.

Forms are the final product of your data. It should look presentable and easy to understand. A form will make the information look professional and makes the data unique. With the forms, all data would look the same in every table, every database in every company. Forms will create varieties in designs.

Reports will be based on the data that has been entered. It is going to summarise the data entry and make the data easy to identify. Reports of the database act as a summary and make the information easier to collect. Open data and go to design tab, add a group and click sort.

3.

The foreign key acts as a reference between two entities or tables. The foreign key is a linkage that connects a secondary table to a parent table. The foreign key does not have to have the same name as the primary key.

Part C

Types of queries

A select query retrieves data from one or more of the tables in your database, or other queries there, and displays the results in a datasheet. You can also use a select query to group data, and to calculate sums, averages, counts, and other types of totals.

A parameter query is a type of select query that prompts you for input before it runs. The query then uses your input as criteria that control your results. For example, a typical parameter query asks you for starting high and low values, and only returns records that fall within those values.

A cross-tab query uses row headings and column headings so you can see your data in terms of two categories at once.

An action query alters your data or your database. For example, you can use an action query to create a new table, or add, delete, or change your data.

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