ABAP program to find BI lookups and code Patterns
http://wiki.sdn.sap.com/wiki/display/BI/ABAP+program+to+find+BI+lookups+and+code+Patterns
Monday, February 20, 2012
Thursday, February 2, 2012
How to Create a Good InfoCube
Try to limit the number of records in the dimension tables. Use the following guidelines:
1. If an InfoObject has almost as many distinct values as there are entries in the fact tables, the dimension this InfoObject belongs to should be defined as a line item dimension. If the dimension is defined in this manner, the system will write the data directly to the fact table instead of creating a dimension table that has almost as many entries as the fact table.
On the other hand, if there are several dimension tables with very few entries (for example, less than 10), these smaller dimensions should be combined into one dimension
2. Group related characteristics into one dimension only. Unrelated characteristics can use too much disk space and cause performance problems (for example, 10,000 customers and 10,000 materials may result in 100,000,000 records).
3. Avoid characteristics with a high granularity, that is, many distinct entries compared with the number of entries in the fact table.
4. Remove all "High-Cardinality" indicators from the InfoCube definition,generally, a dimension has a high cardinality if the number of dimension entries is 20% (or more) of the number of fact table entries. When in doubt, do not set a dimension with high cardinality
5.Because it is far better to have many smaller dimensions than a few large dimensions, I suggest you identify the most dynamic characteristics and place them in separate dimensions. The current size of your dimensions can be monitored in relation to the fact table by running report SAP_INFOCUBE_DESIGNS in transaction SE38 for live InfoCubes This shows the size of the fact table and its associated dimension tables. It also shows the ratio percentage of fact to dimension size.
1. If an InfoObject has almost as many distinct values as there are entries in the fact tables, the dimension this InfoObject belongs to should be defined as a line item dimension. If the dimension is defined in this manner, the system will write the data directly to the fact table instead of creating a dimension table that has almost as many entries as the fact table.
On the other hand, if there are several dimension tables with very few entries (for example, less than 10), these smaller dimensions should be combined into one dimension
2. Group related characteristics into one dimension only. Unrelated characteristics can use too much disk space and cause performance problems (for example, 10,000 customers and 10,000 materials may result in 100,000,000 records).
3. Avoid characteristics with a high granularity, that is, many distinct entries compared with the number of entries in the fact table.
4. Remove all "High-Cardinality" indicators from the InfoCube definition,generally, a dimension has a high cardinality if the number of dimension entries is 20% (or more) of the number of fact table entries. When in doubt, do not set a dimension with high cardinality
5.Because it is far better to have many smaller dimensions than a few large dimensions, I suggest you identify the most dynamic characteristics and place them in separate dimensions. The current size of your dimensions can be monitored in relation to the fact table by running report SAP_INFOCUBE_DESIGNS in transaction SE38 for live InfoCubes This shows the size of the fact table and its associated dimension tables. It also shows the ratio percentage of fact to dimension size.
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