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
The process of keeping information uniform.
Data redundancy in a database means that the same data is present in more than one table.
Data integrity is when data is accurate, with no variation from the original data.
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.