Solving Operational Business Intelligence with InfoSphere Warehouse Advanced Edition

280 Solving Operational Business Intelligence with InfoSphere Warehouse Advanced Edition

Using the debug capability

When debugging your data flow, breakpoints can be set at the object level.

Sample rows and variable state and values can be viewed when the breakpoint

is reached, as shown in Figure 7-5.

Figure 7-5 On breakpoint, options exist to Resume, Continue to end of data flow, or

Cancel

7.3.3 SQW and temporal tables

SQW supports and provides tooling for slowly changing dimensions (SCDs) in

the dimensional modelling sense. When implementing temporal tables as

described in Chapter 5, “Temporal data management and analytics in an

operational warehouse” on page 173, remove any SCD processing in your ETL

engine and use the temporal functionality instead.

For example, to introduce SCD processing to a table, a database designer might

add the columns <EFFECTIVE_START_DATE>, <EFFECTIVE_END_DATE>,

and <IS_CURRENT>. An update to a row in the table using traditional SCD

techniques does the following:

1. Updates the <EFFECTIVE_END_DATE> and <IS_CURRENT> column

values of the existing row.

2. Generates a new row in the table with the new values.

In contrast to Figure 5-4 on page 184, Figure 7-6 on page 281 shows how a

traditional SCD might look. Two rows exist for the same CUSTOMER_ID. The