Examine the Structure
of the New Time Dimension
Having
created our cube, we can overview the Time dimension we have added, to
ascertain that the structure appears to meet our needs.
1.
Within the
Dimensions pane (in the lower left corner of the Cube Structure tab),
expand the Date 1 dimension (named Date 1 by default, since a
dimension named Date already exists within the UDM), by clicking
the “+” sign to its immediate left.
Here
we can see both the “cloned” and alternate Date hierarchies, as before,
as depicted in Illustration 22.
Illustration
22: The Date Dimension (“Date 1”) in the Dimensions Pane ...
2.
Click Edit
Date 1, which appears just under the expanded Date 1 dimension.
The Dimension
Structure tab for the new Date dimension opens, and appears similar
to that shown in Illustration 23.
Illustration
23: The New Date Dimension within the Dimension Structure Tab (Compressed
View)
Here we
can see details about the makeup of the dimension, including Attributes,
Hierarchies and Levels, and so forth. We can also examine, and
modify as desired, the Properties for each respective object. We will
not make any changes for the purposes of our practice exercise; we will leave
everything as defined at this stage.
Generate the
Underlying Schema for the Cube Model
Because
we have designed our cube in “top-down” fashion, it has no underlying
relational database, and, therefore, no underlying data. The next step in
a typical design and development evolution (that is, when using the “top-down”
approach) would be to generate the underlying relational schema, and then to
populate it with data (which would usually be loaded via extraction,
transformation, and loading (ETL) processes) from one or more
operational / transactional / other external data sources.
We will
generate a schema with the rudimentary cube that we have, as a means of
illustrating the process; in some cases, as we have noted, this might provide a
quick and easy means of generating a Time dimension table which is based
upon a structure we have designed within the cube model. This “push-down”
method of table construction is not only quick and easy; it assists us in
building a table that is guaranteed to support our dimensional design, once
populated appropriately (and, as we shall see, population can be set to occur
automatically). Once we had generated a table to support the Time
dimension, say in a target database created especially to contain such a table,
we could move the table(s) to another place, delete the empty tables, etc., as
our needs dictated.
1. Within the Cube Structure
tab, click the link Click here to generate data source view, appearing
in the middle of the Diagram pane, as depicted in Illustration 24.
Illustration 24: “Click
Here to Generate Data Source View ...”
The
initial page of the Schema Generation Wizard appears, as shown in Illustration
25.
Illustration
25: The Schema Generation Wizard Initializes ...
2.
Click Next.
3.
On the Specify
Target page that appears next, click New.
The
first page of the Data Source Wizard (titled Welcome to the Data
Source Wizard) opens next, and appears as depicted in Illustration 26.
Illustration 26: The
Data Source Wizard is Launched ...
4.
Click Next.
5. Click New on the Select
how to define the connection page that appears next, as shown in Illustration 27.
Illustration 27: Create
a Data Source Based upon a New Connection
The Connection
Manager appears.
6.
Type / select the
correct server / instance name into the Server name box of the dialog.
7.
Ensure that
authentication settings are correct for the local environment.
8.
In the Connect
to a database section, under Select or enter a database name, select
DBJ_Schema_Target, the target database we created in our preparation
section earlier.
The Connection
Manager appears, with our input, as depicted in Illustration 28.
Illustration 28: The
Connection Manager with Our Input
9.
Click the Test
Connection button.
A
message box appears, indicating that the Test connection succeeded,
assuming that our changes (or lack of same, as appropriate) are appropriate.
The message box appears as shown in Illustration 29.
Illustration 29: Testing
Positive for Connectivity ...
10. Click OK to dismiss the
message box.
11. Click OK to accept changes,
and to dismiss the Connection
Properties dialog.
» 