Intro and Understanding Databases

Question 1

What are databases?

Answer 1

They are structured systems that allows us to impose our own rules on stored data to suit our needs

Question 2

Why do you want a database?

Answer 2

Allow us to:

1. Scale data stores
2. Make data accessible
3. Make data accurate
4. Make data more secure
5. Make data consistent
6. Make data permanent

Question 3

What problems can arise WITHOUT a database?

Answer 3

1. Size - stored data can rapidly grow and a lack of database can make it difficult to manage this data
2. Ease of updating - file based data storage systems can be slow and inconvenient
3. Accuracy of data - Data can be incorrectly added/inconsistent/untrustworthy
4. Security of data - Data can be sensitive and only some people should be given access and logs may be needed
5. Redundancy - Redundancy between data stores is good BUT can lead to conflicts between different data stores
6. Importance of the data - Key data can be lost and be VERY detrimental to company/project

Question 4

Common database management systems (DBMS)

Answer 4

Oracle
SQL Servers
MySQL
PostgreSQL
MongoDB

Question 5

DIfference between a database and a database management system (DBMS)?

Answer 5

The database management system (DBMS) is installed on a personal computer or server.

The database is created within DBMSs and it is your data

Question 5

DIfference between a database and a database management system (DBMS)?

Answer 5

The database management system (DBMS) is installed on a personal computer or server. It is the program or set of programs that surround and manage the database to ensure that the constriants applied to database are applied.

The database is created within DBMSs and it is your data and rules imposed on this data.

One DBMS can manage MULTIPLE databases

Question 6

Database managment systems can be categorised into different types

Answer 6

Relational DBMS (Oracle, SQL Server, DB2, MySQL, PostgreSQL, SQLite, MS Access)

Hierarchical DBMS

Network DBMS

Object-Oriented DBMS

NoSQL DBMS (Cassandra, CouchDB, MongoDB)