P1/M1– Explain the features of a relational database.
This report is about how relational databases are useful for companies and customers and
its benefits and drawbacks. Some of the features I am going to explain will be: Multiple
tables, one fact in one place, Referential Integrity, Primary Keys, Foreign Keys and
Normalisation.
Features
Relational databases can be made up of multiple tables whereas a flat file which is only
made up of one table. Relational databases are linked via 3 ways which are 1-1 (This can
only be matched once such as customers and order), 1-Many (for example you as a
customer could have many different credit cards) or Many-Many (for example the data in
table A can connect to many rows in table B) However the many too many relationship
should be converted into 1-1 or 1-Many’s so it’s more simpler. Each table has a primary key
which is used to identify the different information in that table for example the primary key of
a table could be customer ID which will include further information such as address, name
etc. Then the primary key can link different tables together when it’s linked with that table its
called a foreign key because this key belongs to another table. Another important feature a
relational database has is normalisation which removes data that is not important or data
that is duplicated. Normalisation can be done in 3 different ways this will make sure there is
only one fact in one place and you won’t find the same information again.
Benefits
The benefits of relational databases:
Reduced storage space- There are many benefits for the user for a relational database
such as a smaller file size because all of the data is stored in relatively easy tables so you
don’t need complex huge tables, also this is much more convenient to a paper based system
because it uses less space and time. Furthermore because another feature of Microsoft
access is normalisation it removes duplicated data so the overall size will be smaller
because it removes data that is repeated.
Ease of Use- Relational databases are easy for a user to use because you can access the
data more easily and do multiple things at the same time. For example there are different
search options were you can search for multiple items and the database will search
everything for you so you as the user will not have to look through everything separately.
Furthermore it also has a GUI interface so it’s simple and easy for the user to use because
it’s more appealing than a person looking at a code view of a table which might confused
them even further. Also because relational databases are linked via relationships and
primary/ foreign keys it makes finding data easier because the relevant data is linked
together from these ways.
Flexibility- Relational Databases allow the user to do basic things such modify, adapt, and
delete with relative ease. For example so for instance you want to delete certain data that is
not needed anymore you can delete the primary key from one table everything linked to the
key will also be deleted so you will not have unnecessary data. Relational databases also
allow different ways of doing the same thing which is useful if you find a certain way of doing
something more useful than another way.
Security- You can add many security features in a relational database for people to stop
editing or deleting your work. For example some of the things you can add is password to
the data to stop people from people you don’t know accessing your work so without the
password they can’t read or modify the file, also you can change the password when you
like. Another security feature you can add is you can lock the tables so they can’t be edited
or deleted this could be useful if some data in the table is very important. Furthermore there
are other options you can take to protect the database such as hiding the database window
This report is about how relational databases are useful for companies and customers and
its benefits and drawbacks. Some of the features I am going to explain will be: Multiple
tables, one fact in one place, Referential Integrity, Primary Keys, Foreign Keys and
Normalisation.
Features
Relational databases can be made up of multiple tables whereas a flat file which is only
made up of one table. Relational databases are linked via 3 ways which are 1-1 (This can
only be matched once such as customers and order), 1-Many (for example you as a
customer could have many different credit cards) or Many-Many (for example the data in
table A can connect to many rows in table B) However the many too many relationship
should be converted into 1-1 or 1-Many’s so it’s more simpler. Each table has a primary key
which is used to identify the different information in that table for example the primary key of
a table could be customer ID which will include further information such as address, name
etc. Then the primary key can link different tables together when it’s linked with that table its
called a foreign key because this key belongs to another table. Another important feature a
relational database has is normalisation which removes data that is not important or data
that is duplicated. Normalisation can be done in 3 different ways this will make sure there is
only one fact in one place and you won’t find the same information again.
Benefits
The benefits of relational databases:
Reduced storage space- There are many benefits for the user for a relational database
such as a smaller file size because all of the data is stored in relatively easy tables so you
don’t need complex huge tables, also this is much more convenient to a paper based system
because it uses less space and time. Furthermore because another feature of Microsoft
access is normalisation it removes duplicated data so the overall size will be smaller
because it removes data that is repeated.
Ease of Use- Relational databases are easy for a user to use because you can access the
data more easily and do multiple things at the same time. For example there are different
search options were you can search for multiple items and the database will search
everything for you so you as the user will not have to look through everything separately.
Furthermore it also has a GUI interface so it’s simple and easy for the user to use because
it’s more appealing than a person looking at a code view of a table which might confused
them even further. Also because relational databases are linked via relationships and
primary/ foreign keys it makes finding data easier because the relevant data is linked
together from these ways.
Flexibility- Relational Databases allow the user to do basic things such modify, adapt, and
delete with relative ease. For example so for instance you want to delete certain data that is
not needed anymore you can delete the primary key from one table everything linked to the
key will also be deleted so you will not have unnecessary data. Relational databases also
allow different ways of doing the same thing which is useful if you find a certain way of doing
something more useful than another way.
Security- You can add many security features in a relational database for people to stop
editing or deleting your work. For example some of the things you can add is password to
the data to stop people from people you don’t know accessing your work so without the
password they can’t read or modify the file, also you can change the password when you
like. Another security feature you can add is you can lock the tables so they can’t be edited
or deleted this could be useful if some data in the table is very important. Furthermore there
are other options you can take to protect the database such as hiding the database window
