Dimension Table and Fact Table

The fact table contains business facts (or measures), and foreign keys which refer to candidate keys (normally primary keys) in the dimension tables. Contrary to fact tables, dimension tables contain descriptive attributes (or fields) that are typically textual fields (or discrete numbers that behave like text).

1. What is a fact table and dimension table example?
2. What is dimension table with example?
3. How do you create a fact table and dimension table?
4. What goes in a fact table?
5. What is difference between fact table and dimension table?
6. What are different types of fact tables?
7. What are different types of dimension table?
8. What are the first 3 dimensions?
9. What is meant by dimensions of a table?
10. Can you join two fact tables?
11. Can a table be both fact and dimension?
12. Can fact table have primary key?

What is a fact table and dimension table example?

Dimension table Dimension table is a table which contain attributes of measurements stored in fact tables. This table consists of hierarchies, categories and logic that can be used to traverse in nodes. Fact table contains the measurement of business processes, and it contains foreign keys for the dimension tables.

What is dimension table with example?

A Dimension Table is a table in a star schema of a data warehouse. Data warehouses are built using dimensional data models which consist of fact and dimension tables. ... For example, a large credit card company could have a customer dimension with millions of rows.

How do you create a fact table and dimension table?

Creating Fact and Dimension Tables from a Single Table or View

1. In Data Modeler, lock the model for editing.
2. In the Database menu in the left pane, right-click the source table that contains the fact and dimensional data that you want to model, select Add to Model, and then select Add as Fact and Dimension Tables.

What goes in a fact table?

In data warehousing, a fact table consists of the measurements, metrics or facts of a business process. It is located at the center of a star schema or a snowflake schema surrounded by dimension tables. ... The primary key of a fact table is usually a composite key that is made up of all of its foreign keys.

What is difference between fact table and dimension table?

The fact table contains business facts (or measures), and foreign keys which refer to candidate keys (normally primary keys) in the dimension tables. Contrary to fact tables, dimension tables contain descriptive attributes (or fields) that are typically textual fields (or discrete numbers that behave like text).

What are different types of fact tables?

There are three types of fact tables:

• Transaction Fact Table. The transaction fact table is a basic approach to operate the businesses. ...
• Snapshot Fact Table. The snapshot fact table describes the state of things at a particular time and contains many semi-additive and non-additive facts. ...
• Accumulated Fact Sheet.

What are different types of dimension table?

Dimension: A dimension table has two types of columns, primary keys and descriptive data. For example, Time and Customer.

What are the first 3 dimensions?

Let's start with the three dimensions most people learn in grade school. The spatial dimensions—width, height, and depth—are the easiest to visualize. A horizontal line exists in one dimension because it only has length; a square is two-dimensional because it has length and width.

What is meant by dimensions of a table?

A dimension table stores attributes, or dimensions, that describe the objects in a fact table. In data warehousing, a dimension is a collection of reference information about a measurable event. These events are known as facts and are stored in a fact table. ... Dimension tables are referenced by fact tables using keys.

Can you join two fact tables?

The answer for both is "Yes, you can", but then also "No, you shouldn't". Joining fact tables is a big no-no for four main reasons: 1. Fact tables tend to have several keys (FK), and each join scenario will require the use of different keys.

Can a table be both fact and dimension?

Additionally, any table in a dimensional database that has a composite key must be a fact table. This means that every table in a dimensional database that expresses a many-to-many relationship is a fact table. Therefore a dimension table can also be a fact table for a separate star schema.

Can fact table have primary key?

The fact table's primary key is made up of the primary keys of all the dimension tables. The primary key of the REVENUE fact table, which is a concatenation of the primay keys of the dimension tables, can uniquely identify each row.