OAC―Knowing the Dimensional Modelling Basics (2/2)

Video 1. Create your initial data model from Relational Sources using Data Modeler

Video 2.  Create Time Dimension Tables Using Data Modeler

In a previous article "OAC―Knowing the Dimensional Modelling Basics (1/2)", we have covered basic concepts of dimensional modeling:

• Transactional versus Analytical Systems
• Data Warehousing
• Dimensions, Facts and Hierarchies

In this article, we will cover how Dimensional Modelling works in Oracle Analytics Cloud (OAC).

Figure 1.  Open Data Modeler in Oracle Analytics Cloud by clicking the action menu

Data Modeler

Using Data Modeler (see Figure 1) you can model data from various source types, such as star and snowflake, in various ways that make sense to business users.

Although not all source objects have star relationships, Data Modeler presents data as a simple star structure in the data model. In other words, the data model represents measurable facts that are viewed in terms of various dimensional attributes.

If you modeled your business data with Oracle BI Enterprise Edition, you don't have to start from scratch with Data Modeler. You can upload your data model to the cloud.^[14]

Figure 2.  Left Pane in Data Modeler

Figure 3.  Action menu associated with Objects in Data Modeler

Figure 4. Create Data Model in OAC

Video 3.  Create Hierarchies for Dimension Tables Using Data Modeler

Data Modeling Tasks

When building a data model in OAC, you perform the following tasks:^[3]

• Connect to the database containing your business data
• In Data Modeler, the left pane shows the Database, Data Model, Variables, or Roles menu (see Figure 2).
• Action menus contain actions that are relevant for a particular object or context, and are visible when the object is selected.
• For example, if a source object in the Database menu is selected, its action menu shows: Add to Model, Inspect, and Duplicate (see Figure 3).
• Add source tables or views to the model and classify them as either a fact table or a dimension table. 
• After you have started modeling data, the right pane in Data Modeler shows the fact tables, dimension tables, and joins (see Figure 4)
• The right pane in Data Modeler is a contextual pane that changes depending on what task you’re performing. 
• Define joins between fact and dimension tables 
• Ensure Correct Mapping 
• Every dimension table maps to at least one fact table, and that every fact table maps to at least one dimension table. 
• Edit object with its editor
• Specify aggregation rules for different fact columns
• Create derived measures based on expressions
• Create dimension hierarchies to support drilling
• See video 3
• Create level-based measures. 
• Publish data model 
• To permanently save the changes and make the data available for use in analyses
• When your HTTP browser session times out (after 20 minutes of inactivity), the lock is released and any unpublished changes are discarded.
• Similarly, closing a browser ends the HTTP session and discards any unpublished changes. 

Figure 5.  Create project in Oracle Analytics Cloud to use newly published data model (see video 1&2)

Figure 6.  Published Cust Rev Model displayed as a Subject Area

Visualizations / Dashboards / Analyses

After publishing your data model, you can start visualizing your data from your enterprise reporting Home page (see Figure 5 and watch video 1). Your data model displays as a subject area that you can use in visualizations, dashboards, and analyses (see Figure 6). The name of the subject area matches the name of your data model.

When you model source objects with multiple star relationships, they’re all part of the same data model and are included in the same subject area. 

Video 4.  Manage What Users Can See and Do in Oracle Analytics Cloud

Figure 7.  Use Console to create and manage application roles

Figure 8.  Configure application roles from the Administer Users and Roles page in the Console

Figure 9.  Application Roles tab shows predefined and custom application roles

Figure 10.  Add new members or remove members from an application role

Application Roles

You must have the BI Data Model Author role (including table access permissions) to author data models.

Predefined Application Roles in Oracle Analytics Cloud	Description	Default Members	Predefined Application Role in Oracle Identity Cloud Service Foot 1
BI Service Administrator	Allows users to administer Oracle Analytics Cloud and delegate privileges to others using the Console.	Administrator who created the service	ServiceAdministrator
BI Data Model Author	Allows users to manage data models in Oracle Analytics Cloudusing Data Modeler	BI ServiceAdministrator	ServiceAdministrator

Administrators configure what users see and do in Oracle Analytics Cloud from the Administer Users and Roles page in the Console (see Figure 7&8). This page presents user information in 3 different views:

Users and Roles Page	Description
Users tab	Shows users from the identity domain associated with your service. You can add users, delete users, and assign users one or more application roles in Oracle Analytics Cloud.
Roles tab	Shows roles from the identity domain associated with your service. You can add and remove roles (groups of users), and assign them to one or more application roles in Oracle Analytics Cloud. From the Roles tab you can also see who belongs to each role.
Application Roles tab	Shows predefined application roles for Oracle Analytics Cloud together with any custom application roles you define. From the Application Roles tab you can assign application roles to multiple users, roles, and other application roles. You can also create application roles of your own and assign privileges to them through other application roles.

You select members for an application role or change parent privileges using the Console.

1. Click Console (see Figure 7).
2. Click Service Administration, and then click Administer Users and Roles (see Figure 8).
3. Click the Application Roles tab (see Figure 9).
4. To display all available application roles, leave the Search field blank and Show Members: All.  To filter the list by name, enter all or part of an application role name in the Search filter and press Enter. The search is case-insensitive, and searches both name and display name.
5. Look in the Members area to see who belongs to each application role:
• The number of users, roles, and application roles that are members displays on the page. Click a number, such as 5 in this image, to see those members in more detail (either users, roles or application roles).
6. To add new members or remove members from an application role (see Figure 10):
1. Click Members.
2. Select either users, roles, or application roles from the Type box and click Search to show the current members.
3. Use the shuttle controls to move members between the Available and All Selected list.
• Some application roles aren't eligible to be members and these are grayed. For example, you can’t select a parent application role to be a member.
4. Click OK.
7. To see whether an application role, such as Sales Analyst, inherits privileges from other application roles:
1. Click the action menu.
2. Select Manage Application Roles.
• Inherited privileges are displayed in the Selected Application Roles pane. (see Figure 11)
8. To add or remove privileges:
1. Click Search to display all available application roles.
• Alternatively, enter all or part of an application role name and click Search.
2. Use the shuttle controls to move application roles between the Available Application Roles list and the Selected Application Roles list.
• You can’t select application roles that are grayed out. Application roles are grayed out so you can’t create a circular membership tree.
3. Click OK.

Figure 11.  User Ed Ferguson was assigned with the Sales Analysts application role

References

1. OAC―Knowing the Dimensional Modelling Basics (1/2)
2. Model Data for Reports (OAC)
3. Use Data Modeler (OAC)
4. Oracle® CloudPreparing Data in Oracle Analytics Cloud
5. OAC―Knowing Machine Learning Basics
6. Data Visualization (Forum)
7. Oracle Data Visualization Desktop (Documentation)
8. OAC―Loading Data with Data Sync
9. Edit Hierarchies and Levels (OAC Data Modeler)
10. Get Started with Oracle Data Visualization V5 (YouTube)
11. Explore Data in Oracle Data Visualization V5 (YouTube)
12. Create Data Flows in Oracle Data Visualization V5 (YouTube)
13. Data Science for Business (Safari)
14. Upload Data Models from Oracle BI Enterprise Edition
15. Learn Modern Data Visualization with Oracle Analytics
16. Click here for more A-Team Oracle Analytics (OAC) Blogs.