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Building a Database. Database. What is database ?. a collection of data or information that is organized so that its contents can easily be accessed, managed, and updated. Type of database. Manual database Computerized database.
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Building a Database Database
What is database ? • a collection of data or information that is organized so that its contents can easily be accessed, managed, and updated.
Type of database • Manual database • Computerized database What is the difference between manual database and computerized database?
Manual database • Lists created on stone, metal or paper are called manual database. • Example: List students’ mark. The list consists two columns, NAME and MARKS. Teacher fill in the names and marks for each subject according to level : year 7, year 8 etc. These paper files are then stored in filling cabinet.
Manual database Disadvantages : • Accesing file and updating is very time consuming. for example when data needs to be retreived or updated, the user has to search through file to locate them physically. • Take up a lot of space since data has to be stored files.
Computerized database • Store data and manipulate a database using computer .
Computerized database Advantages : • Store information only once since most database software allows you to access information from several files. • Validation checks may be made on the data so that there will be fewer errors in the data. • Files can be linked together, which means that if you update one of the files, all the other files that depend on the same information will automatically be updated. • Access information is quickly.
Computerized database Disadvantages : • If the computer breaks down, you are not able to access the details. • It is easy to copy computer files. • Training is needed to use system so that this takes time and cost money • Database may be corrupted / infected. • Some database complicated to us.
Parts of database Databases are organized in files which consist of a series of records which in turn consist of a series of fields. Once your understood this, you will be well on the way to understanding database.
Parts of database • Files - a collection of data or information that has been given a name.
Parts of database • Records – one entry in a database.
Parts of database • Fields – records contains a number of fields. ( each item in a record )
Parts of database : Scenario 1. Information of all student s in a school could be save as student file 2. Student record card - record 3. Student number, forename, form, DOB – field name
Two main types of database • flat file database • relational database
ACTIVITY • Activity 1 – brain storming • Activity 1 – fill in he blanks • Homework