Database concept

Database concept

1. A database is a persistent, organised store of related data

   • A database is persistent because the data and structures are stored in secondary storage

2. Computerised database- a collection of related data stored in one or more computerised files in a manner that can be accessed by users or computer programs

   • Computerised databases have advantages over manual
     • Can be accessed by more than one person at the same time
     • Ability to query/interrogate data and view results
     • Changes to data made quickly and avaliable to all users
     • Processing accuracy of data handling software reduces errors in repetitive tasks
     • Data can be output in different formats to suit user (graphs, report)

3. Database maintenance

   • adding (also referred to as inserting) new data records (for example, when a new member of staff joins a company or a new product is added to the stock in a warehouse)
   • deleting existing data records (for example, when a member of staff leaves a company or a product discontinued from the stock in a warehouse).
   • updating (editing) existing data items within existing data records (for example, when a member of staff changes their name or a product has a price change).

4. Database interrogation involves using the database management software to query (search) the database for information.

   • A query design specifies which records the user is searching for and what fields to display out of those records.
     • Complex query - looking for data in multiple fields
     • Simple query - looking for data in one field only

5. Database creation

6. Any software designed to create, maintain and interrogate computerised databases is termed data handling software.

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