InfoCube Design Alternative I Time-Dependent Navigational Attributes

In the Part I InfoCube design, IO_SREG and IO_SOFF are in a hierarchy of IO_SREP as the hierarchy's node values (Screen 3.46). In this section, we will discuss an alternative by putting IO_SREG and IO_SOFF into a new IO_SREP, or IO_SREPN1, as time-dependent navigational attributes.

First, we show how to build this new design.

Work Instructions

Step 1. In the definition of IO_SREPN1, append IO_SOFF and IO_SREG after the existing IO_SREPNM as attributes.

Make IO_SOFF and IO_SREG time-dependent by selecting the corresponding rows in the column Time-Dependent. Click graphics/timedependent.gif to switch them from display attributes to navigational attributes.

 

 

SCREEN 7.12

graphics/07fig12.gif

Step 2. Enter the description Sales office for the navigational attribute IO_SOFF, and Sales region for IO_SREG.

(Screen 7.13 shows the description for IO_SOFF only.)

 

 

SCREEN 7.13

graphics/07fig13.gif

Step 3. Click graphics/check.gif to check the InfoObject. If it is valid, click graphics/activate.gif to activate the InfoObject. The time-dependent master data table /BIC/QIO_SREPN1 and the time-dependent SID table /BIC/YIO_SREPN1 are created. Their names appear in the Time-dependent master data tables block.

 

 

SCREEN 7.14

graphics/07fig14.gif

Step 4. Double-click the SID table /BIC/YIO_SREPN1 to reach its definition screen.

Here we see two time-related fields, DATETO and DATEFROM. When we load data, we use these two fields to specify a record's valid period. DATETO is part of the key that makes a record unique.

We also see two other SID fields, S__IO_SOFF and S__IO_SREG. BW uses them to link IO_SREPN1 to IO_SOFF and IO_SREG, moving IO_SOFF and IO_SREG one more level away from the fact table. This layout will negatively affect query and load performance.

 

 

SCREEN 7.15

graphics/07fig15.gif

Step 5. Follow the work instructions in Section 2.5 to create a new InfoCube called IC_NEWBC1. In the InfoCube definition, click graphics/navattributes.gif to specify the navigational attributes.

 

 

SCREEN 7.16

graphics/07fig16.gif

Step 6. In the pop-up window, check the I/O column to activate the two attributes, and then click graphics/continue.gif to continue.

 

 

SCREEN 7.17

graphics/07fig17.gif

Step 7. After checking, activating, and loading data into the new InfoCube, we can create a query.

In the left panel, we see that Sales office (navigational attribute), Sales region (navigational attribute), and Sales representative (characteristic) all reside in the same dimension. From the query point of view, the navigational attributes are just like their characteristic, allowing for drill-down.

Click graphics/legendicon.gif to specify a key date.

 

 

SCREEN 7.18

graphics/07fig18.gif

Step 8. Enter 31.12.9999 as the key date, and then click graphics/ok.gif to continue.
 

SCREEN 7.19

graphics/07fig19.gif

Result

The query result shows that the Denver office is located in the West region (Screen 7.20).

SCREEN 7.20

graphics/07fig20.gif

Create another query, but this time enter 31.12.1999, instead of 31.12.9999, as the key date (Screen 7.19). Screen 7.21 displays the result of the new query, which shows that the Denver office is now located in the Midwest region.

SCREEN 7.21

graphics/07fig21.gif

Note

Based on our discussion, we can draw a simplified star schema as shown in Figure 7.2 for this design alternative.

Figure 7.2. BW STAR SCHEMA OF ALTERNATIVE I INFOCUBE DESIGN

graphics/07fig02a.gif

In Figure 7.2, /BIC/SIO_SREG and /BIC/SIO_SOFF have their own master data table and text table. These tables are not shown in the figure.

Because IO_SREG and IO_SOFF are placed one level farther away from the fact table, query performance will be poor with this design.

Because IO_SREG and IO_SOFF are hidden inside IO_SREPN1, we cannot build aggregates on IO_SREG and IO_SOFF.

Navigational attributes facilitate system maintenance. For example, if we need to reassign sales offices and sales regions, we can create new records in the master data table with corresponding valid dates.

This design, however, is not flexible enough to permit structure changes, because the levels of the sales organization are fixed.

Part I. Guided Tours

Business Scenario and SAP BW

Creating an InfoCube

Loading Data into the InfoCube

Checking Data Quality

Creating Queries and Workbooks

Managing User Authorization

Part II. Advanced Topics

InfoCube Design

Aggregates and Multi-Cubes

Operational Data Store (ODS)

Business Content

Generic R/3 Data Extraction

Data Maintenance

Performance Tuning

Object Transport

Appendix A. BW Implementation Methodology

Object Transport

Appendix B. SAP Basis Overview

Object Transport

Appendix C. Glossary

Appendix D. Bibliography



SAP Bw. A Step-By-Step Guide
Sap Bw: a Step By Step Guide for Bw 2.0
ISBN: B000LZM8CM
EAN: N/A
Year: 2002
Pages: 106

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