Information Systems Design and Development

HideShow resource information

Database

DB - A collection of related information organised in such a way that it is easy to search and sort.

1 of 8

Data Dictionary

DB - A grid showing the databse design for each table in the database and within each table, each field, its type and other attributes.

2 of 8

Flatfile Database

DB - a database that is made up a single table

3 of 8

Relational Database

DB - a database that is made of more than one table that are linked to each other by some form of relationship

4 of 8

Database User Interface

what the user will see on the screen and how they will interact with the software when using a database.

- Table: a list of the fields that will be stored about a single entity

- Form: the user interface for a database that is used to enter or amend data

- Report: the result of applying a query to a database - this may also include derived data to group or summarise the results. Wire-framming may also be used to design a report.

- Navigation Form (Switchboard): a form that appears when the database is loaded. It hides the commands and structre of the database from the user and contains 'buttons' to carry out the tasks that the user will be permitted to use on the database. Each 'button' when 'clicked' runs either a macro or a programmed script to carry out its action. This allows inexperienced users to perform complex actions on the database with littl eor no knowledge of the database itself. 

5 of 8

Database Queries

Used to search a database to specific information

- Calculations: a query can include a 'derived field' - this is a field that does not appear in any of the tables but derives its contents from carrying out some form of expression (a calculation or summary) on chosen fields within the database. 

- Select: a select query is used to extract information from a database and present it to the user, in order to answer a question posed by the user - this may involve carrying out searches and sorts on the data and choosing the fields to display.

- Update: an update query is used to change the data in a database or to change the structure of a database.

6 of 8

Relationship

this is the link between two different tables in a relational database.

 - Primary Key: the field that uniquely identifies a record in a relational database is linked to a      foreign key in another table to form a relationship between the tables.

- Foreign Key: a field in one relational database table that corresponds to the primary key in another table in the database and is used to form the relationship between the two tables.

- Compound Key: where more than one field is used to uniquely identify a record in a table - often each individual field is also acting as a foreign key to seperate tables.

- One-to-one: each record in a table is related to one other record in another table.

- One-to-many: each record in a table is related to more than one record in another table.

-Many-to-many: many records in one table are related to many records in another table.

Entity Relationship Diagram: a diagram showing the tables makingup a relational database with the primary keys linking to the corresponding foreign keys and the types of relationships involved. 

7 of 8

Scripting Language

a scripting language is a full programming language that is executed by an interpreter built-in to the database management software.

8 of 8

Comments

No comments have yet been made

Similar Chemistry resources:

See all Chemistry resources »See all Information Systems Design and Development resources »