week 10
Learning Aims and Objectives:
Aim: In this week's page, students will learn .
Objectives:
1. By the end of this week's page students will be able to
2. By the end of the week's page students will be able to
3. By the end of the week's page students will be able to
4. By the end of the week's page students will be able to
5. By the end of the week's page students will be able to
Client-Side Processing
In the area of the website development and design the creator/author of the website will use what is known as Client-side processing to enable the use of some code to run on the machine viewing the website. Why is this of value?
lets look at the processing of data, it can take time to send information back and forth between cleints and servers , this can take up valuable bandwith from both sides. A good example of this is where a use is inputting information like thier email address, if the user enters this wrong it could affect the whole registration of a new user to a membership of a blog or even to log in. So checks are put in place to make sure that the email is using the correct layout, so it has and @ sign and .co.uk or any other version of a top level domain.
Could you imagine Facebook, all the new users on facebook entering the email address information wrong on the sign up page this information is sent to the server, the server then checks the information, it realises that this is wrong and sends a message back to the user. If it has to do this on a number of requests the server will slow down and could crash.
So we use client sidde processing to run these checks, this information is not sensitive, however we would NOT check the password on the client side due to security.
Areas where this processing may happen would be the loading of games and things like role over images where the image changes to another when a users mouse hovers over another image.
Server-Side Processing
Server side procesing happens once a request has been sent it, this could be an original request for a webpage, or it could be the information to login to the system, things like blog, online commerce sites and online email. The server will have a number of pages that are dynamic that can send a customised webpage back to the user based upon the login details that it has recieved. Server sider processing is brower indepentant so it will not worry what browser the user is using at the other end when it sends its responce.
Caution has to be taken when sending information to the server as this is going out over the internet where it can be intercepted.
Servers can crash when put under stress, this could be like when a new product becomes availble for online ordering and millions of users try to access the server at once.
Databases
https://spencerwade.files.wordpress.com/2013/02/a25.jpg
As they say in london you are only a matter of feet from a rat, the same is true of databases.
Databases are every where, from the use of a car park payment system recording the registration number of the cars that are in the car park at a time, to the booking of an appointment at a doctors or dentist.
Databases collect and provide information to users but how do they work? Lets look in to this a little deaper
Databases use areas called tables, these tables are set up by the owner to capture selected information that is required. This table could be set up to gather information on a person, this could have the following "fields" within the table,
- Customer_id
- Name
- Surname
- Address
- DOB (Date of Birth)
Each databases field can be set to only allow certian types of data to be input in to them, these can be;
| Data Type | Description | Example |
|---|---|---|
| Text | Characters, these can be letters number and symbols | WC1 4CJ |
| Number | Number (integers) values only | 123456789 |
| Time/Date | Time and date values | 25/12/2000 |
| Boolean | Yes or No, True or False (binery) | Yes |
Database Relationships
Databases have the ability to make our lives easier, they can tell us things like the current stock levels of a new release of a games or the cost of a train ticket between two locations. This data however is not stored in a single location/table, it is stored acorss a number of them.
Let us consider the following, you live in a house with your parent, therefore you all have the same address, is thie not a waste of time re-entering it over and over again, can i not just reference to it! The answer is Yes!
By using multiple tables we can store information in them that other tables can reference to. So taking our example lets look at the link between them.
Database management systems or DBS systems programs allow you to create databases. Databases use a structured query language or SQL which is a high-level language.
1.data definition language or DDL is used to define the structure of a database
2.data manipulation language or DML is used to add, delete, change and query databases where the data are held.
SQL is the language that is used to run a number of operations on a database management system.
DISCUSSION TIME!!!
FACTIOD:
Last Updated
2024-08-30 10:15:52
Links to Learning Outcomes |
Links to Assessment criteria |
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|---|---|---|
English
Maths
How 2's Coverage
Anonymous Assessment - Learners assess an anonymous piece of work containing deliberate mistakes against given success criteria.
Anonymous Assessment - Learners assess an anonymous piece of work containing deliberate mistakes against given success criteria.
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