Introduction to databases
Learning intentions
You should be able to describe what databases are in clear terms, explain why databases are used for managing information, identify problems with older systems, use basic database terminology, and prepare for database design concepts.
Introduction to databases
Databases are used to organise and manage information
in a structured way so it can be searched and updated efficiently.They store related data electronically
rather than relying on paper records or disconnected files .Databases are commonly used in schools, businesses, and apps
where large amounts of data must be handled .They are more powerful than paper systems because computers search, sort, filter, and find records
much faster than people can manually .Databases are designed for accuracy and efficiency
by applying consistent rules to how data is stored .
Data vs information
Data refers to raw, unprocessed facts
such as names, dates, or numbers .Information is processed data that is meaningful
and useful to people .Databases store data rather than conclusions
so the same data can be reused for different purposes .Data is turned into information using queries
that sort, filter, and combine records .Information is only reliable when the underlying data is accurate
, as errors affect all results .
Problems with paper-based systems
Paper-based systems are slow to search
because records must be checked by hand .Paper records are easily lost or damaged
through misplacement, fire, or water .Paper systems are hard to update consistently
when the same information appears in multiple places .They often contain duplicate information
, which increases the chance of errors .Paper-based systems provide limited security
because access is based on physical location .
Problems with spreadsheet systems
Spreadsheet systems often include repeated data
when the same details are entered many times .They are prone to hidden errors
caused by formulas or copying mistakes .Spreadsheets are not ideal for complex relationships
between different sets of data .They can become slow as they grow larger
and contain more formulas .Spreadsheets offer limited control over data entry
compared with databases .
What a database solves
Databases reduce duplication of data
by storing each fact only once .This improves consistency of information
because updates are made in a single place .Databases make searching faster
by allowing instant queries .They simplify updates and maintenance
through structured tables .Databases support higher data accuracy
by enforcing rules on data entry .
Types of databases
Flat-file databases store all data in a single table
, which limits flexibility .Relational databases use multiple linked tables
to reduce duplication .Single-user databases are designed for one person at a time
, often on one computer .Multi-user databases allow many users to access the same data
at the same time .Database systems range from small classroom projects to large-scale organisational systems
used worldwide .
Database use in everyday life
Schools use databases for enrolment and attendance systems
to track students and classes .Online shopping relies on databases for customer accounts and orders
to manage purchases .Banks use databases to store transaction records
that must be accurate and secure .Healthcare systems rely on databases for medical and patient records
with controlled access .Social media platforms use databases to manage profiles, posts, and interactions
between users .
Manual vs computerised systems
Computerised database systems are faster to search and sort records
than manual systems .They are more reliable for repeated tasks
because rules are applied consistently .Databases make it easier to store large amounts of data
without needing physical storage .They are safer when backups are used
, allowing data to be recovered if something goes wrong .Database systems are better suited to growth over time
as data volumes increase .
Overview of a database system
A database system contains tables that store related data
such as students or bookings .Each table includes fields that describe attributes
like names or dates .Records represent individual items within a table
such as one student .Queries retrieve information from data
by asking specific questions .Reports present information clearly
in a format designed for users .
Review
How well do you feel that you understand what databases are, can explain why databases are used, can identify problems with older systems, and can use basic database terminology?