In
case dimension tables of star schema data model becomes too large comparing to
fact table there can be a performance problems. Thus, it needs to be monitored.
SAP provides a tool for that. It is ABAP program called SAP_INFOCUBE_DESIGNS. The tool provides a list of cubes associated
with number of rows and density % rate for each if the cube.
The
density ratio means a number of rows in the cube fact table divided by the
number of rows in each of its dimension table. The ratio is calculated by DB
specific FM RSDU_INFOCUBE_TABLE_SIZES e.g. RSDU_INFOCUBE_TABLE_SIZES_HDB in
case of HANA DB.
If
the ratio is very high, there should be done something with the cube design. Some
characteristics can be moved to separate dimension. Similarly, if the characteristics
is very large it is be only one in the dimension and the dimension can be
market as line item
dimension.
In
case of BW4/HANA the report is not relevant as source of the information is
table RSDCUBE and there are no cubes in BW/4HANA. Basic infoprovider type of
objects is aDSO
that has flat layout so no star schema anymore. To get to know more information
about the aDSO one can use watermarks
tool.
More
information:
Note 1461926 - FAQ: BW report SAP_INFOCUBE_DESIGNS
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