WEEK 3

• Relational database – it models information and data into a set of tables with rows and columns and it has four stages:
• Relations/Attributes.- the tables represent entites and the attribute represent the properties.
• primary keys – Hels in uniquely identifying a record.
• Relationships – tables are established with the help of foreign keys
• Foreign keys – attributes that occur in a table that are primary in another table.
• Normalization – the process of optimizing the database structure. It simplifies the database and avoids redundancy.
• SQL – used to manipulate relational databases.
• Aggregate functions – it returns one value after calculating multiple values of a column.