Topic 7-Relational databases and SQL Flashcards
What is a database?
A structured and consistent collection of data.
What are the positives of databases?
Makes processing more efficient, reduces storage requirements.
What are the two types of databases?
Relational and flat file.
What is a flat file database?
All data stored on one table.
Characteristics of flat file databases.
Very inefficient, difficult to query and used for small/trivial data sets. Data is often duplicated, also suffers inconsistencies between records. This can compromise the integrity of the data.
What are relational databases?
More than one table that are related, this eliminates data inconsistency and data redundancy.
What are databases manage by?
Data base management system such as access.
What is a primary key?
A field that uniquely identifies a record in a table.
What is a foreign key?
Primary key for one table and foreign key for another table.
