Databases Flashcards
Data integrity
Means that the data reflects realit
Database
Persistent organised store of data on a computer system
What is validation
Is the process of checking data when it is input.
What is verification
Is checking that the data entered is correct
List standard operations on databases
Create
Read
Update
Delete
Data matching
Compares different databases to look for relationships
Data mining
Is a process that looks in many different unrelated databasrs
Flat file database
Rows and columns, row is called a Record and each column a field. Flat file databases are very limited
Relational database
Store data in separate tables, which are linked together so that related data can be easily extracted. Each table contains data about an entity (something in real life about which we store data).
What is a DBMS
Database management system. It:
Connects data and applications
Protects data integrity
Uses record locking to prevent errors in transactions
What are transactions
When a change takes place in a database
Tables
Structures where data is stored. Each table contains data about only one entity. It has a primary key which is the unique identifier. Each column is a particular data type
Relational databases
Databases where tableware linked together
Different data types:
Number Currency Text Date/time Boolean
Forms
Provide a friendly UI to input data more easily
