1. GCSE Computing
Databases

2. Unit Objectives Learn about what databases are.
Learn why databases are so important.
Learn about how relational databases are constructed and used.

3. Today’s Learning Outcomes:
LO1: Identify what a database is. LO2: Be able to define some key features of a database. LO3: Apply knowledge of databases to exam style questions

4. Starter What is a Database?
In pairs come up with a possible definition of a database and give examples of when and what they may be used for.
Open word doc and create new folder for this!

5. Definitions:
A database is a persistent organised store of data on a computer system.
A database is simply a container of information.
A database is a collection of information organized to provide efficient retrieval. The collected information could be in any number of formats (electronic, printed, graphic, audio, statistical, combinations). There are physical (paper/print) and electronic databases.
Possible definitions of a database. The top one coming out of the GCSE computing text book.
In the word document open combine the definitions with your own and write yourself a definition of a database that cover these on the slide and the things people offered in feedback.
Bold definition is the OCR definition of a database (Must know this as minimum):
STORE of DATA: clearly lots of data are being stored in a database.
ORGANISED: more than just a store of data. A graphics file or collection of post it notes on a wall is a “collection of data”. A database has the data organised into records. A school database will have a record per student for example.
PERSISTANT: non-volatile store of data on a secondary storage system such as a hard disk. This is in comparison to an Array which could also be described as an organised store of data but an array exists in memory while a program is running. A database exists on a disk and can be accessed by a program but the database itself is in persistent storage.

6. Examples of databases:
Knowing what a database is can you think of some that people use in everyday life?
A database doesn’t have to be on a computer the simplest example of a database would be someone's address book.
Many examples of where databases are used in everyday life:
Super markets computer systems use databases to monitor stock as soon as the item you have taken of the shelf is scanned it deducts that item of the database so that when stock is low and hits the reorder point more is ordered.
Websites use databases to keep track of information, mostly for Internet commerce or recorded user information and usage.
Google is a huge database of websites.
What others are there?

7. A database can exist with just one table, or a database can have lots of tables.
The main idea here is that each table deals with one sort of item.
A company would have a separate table for their customers, a table of their products, a table of their suppliers, a table of their orders, and so on.
The database is really just a container that holds tables and manages how they can be used.

8. Key Features

9. Field: a single piece of data eg- name, D. O. B, telephone
Field: a single piece of data eg- name, D.O.B, telephone. Record: one complete set of fields eg one pupil’s school File: a collection of records eg a school database. Table: can store many records, from a few dozen for a small database up to millions for a large company database.

10. Activity What’s an entity?
- something that we store data about in a database. Eg Video shop may keep track of customers, invoices, DVD’s, Rents.
What’s an attribute?
-A characteristic of an entity. It becomes a field in a data table.
List the entities you would expect to find on the school database
An entity is something in the real world that we store data about. In this case it is a person or a group of people. An entity can be anything, such as a car, an invoice, a an order or an exam subject. An entity becomes a table in a database. One instance of an entity, such as particular person, is stored as a record in a database.
An attribute is something about an entity. It becomes a field in a database. An example of an attribute is a surname, an invoice number or a car’s colour.

11. Key Database terms
Draw a table that looks like this in your word document:
Entity
Fields
Member Details
Name
Birthdate
Address
ContactNumber
Ben Smith
26/06/89
27 Horseshoe Lane
555666
Rebecca Hill
07/02/91
45 Key Street
234542
Harry Jones
14/12/90
1 Grove Street
987567
Annotate the table with key terms for databases.
Items: In this example, each person is considered an item. In other words, the item is the very thing or things that the database is storing information a
about.
Fields: Each question that we ask about our items is a field. –filed names don’t have spaces, just like programming, it is considered good practice to use pascal case to name fields.
Value: Finally, a value is the actual text (or numerical amount or date) that is used to fill in the blank when adding information to your database.
Record
Items
Value

12. CRUD
A Database is handled by Software. Database software has to be able to: CREATE RETRIEVE UPDATE DELETE
Similar in Python you could do all of these things. You could for instance create an address book in python where you can store data about a person (create it), then call upon it (retrieve it) you can change the program in python to add new data to the file or write different data (update) and you can also delete data that is no longer required (delete).

13. Have the definition of a database
Examples of databases
Entities you would expect to find in a school database.
Have the table drawn showing key features.
Have definitions of key terms

14. Plenary
Write your own exam questions and Mark Scheme for what you have learnt today.