Two Main Types of Databases
According to Mark Long there are two main types of databases. They are the Online Transaction Processing (OLTP) and the Online Analytical Processing (OLAP) databases. Most databases fall somewhere in between these to types.
The course that I’m taking focuses on the OLTP database, and I will mostly be writing about this type for the foreseeable future. OLTP are designed for a high volume of input, but are slow to retrieve data. They allow for simultaneous updates and are quick and responsive to updates. They are normalized . Normalization refers to the way a database is organized, meaning that it has several interconnected tables. These tables are linked though shared key words. Because this database has several interconnected tables it has little wasted space. For example, if a database stores someone name and addresses along with other information, but has two slots for addresses the second address would be on its own table. Thus if someone only had a single address entered in this database it would not be creating and storing an empty slot, and only people with multiple address would appear in the second address table.
OLAP databases are typically called data warehouse or a data mart and are mostly used for data analysis or data mining. I am interested in learning about this database but unfortunately it’s not covered in this course. They are designed for fast retrieval of data but are slower to accept input. They are denormalized. As you might imagine denormalization is basically the opposite of normalization. Therefore in denormalization you have fewer, larger tables that hold data. OLAP databases tend to be very larger than OLTP databases.
