Database management system (DBMS)

What is a DBMS?
Software applications that interact with the user, other applications, and the database itself to capture and analyze data.
What does a DBMS do? (4)
– Allow the database to be defined
– Allow users to query the database
– Allow the user to modify the structure of the database
– Provides adequate security for the data held
What can DBMS do with data?
Allows data to be appended, deleted and edited
Advantages in using a DBMS
– Stores data in a logical and structured way
– Data can be kept separate to the applicants using it
– Avoids data redundancy
– Data integrity is maintained
– Increased security
Disadvantages in using a DBMS
– Learning how to use a DBMS can be difficult
– Costs for the development of a DBMS can be very high
– The whole data is stored in a central location which means it is more vulnerable
Data consistency
The process of keeping information uniform.
Data redundancy
Data redundancy in a database means that the same data is present in more than one table.
Data integrity
Data integrity is when data is accurate, with no variation from the original data.
Data independence
Data independence is a form of database management that keeps data separated from all programs that make use of it
What is the difference between a primary key and a foreign key
PK: A primary key is a special relational database table column (or combination of columns) designated to uniquely identify all table records

FK: A foreign key is a column or group of columns in a relational database table that provides a link between data in two tables. It acts as a cross-reference between tables because it references the primary key of another table, thereby establishing a link between them.