BW: Hints for number range buffering
The number range object of a dimension table should be buffered if
a) the DIM table increases by a large number of data records for each request
b) the size of the DIM table levels out but at the beginning you expected or observed a significant increase
c) there are many accesses to the NRIV table with reference to the number range object of the dimension table
d) the InfoCube or the dimension table is deleted regularly and, therefore, the DIM table increases significantly in each period.
The number range object for the SIDs of an InfoObject should be buffered if
e) you regularly add many new data records to the SID table
f) you know before the initial load that there is a lot of master data to be loaded for this InfoObject
g) you delete the master data periodically and you always load many new records (this should be an exception).
How do you find number range objects of the dimensions and SIDs whose number range should be buffered?
h) You know in advance that the dimension table or the SID table will increase significantly per request.
i) You observe accesses to the NRIV table and you can determine the number range object directly in the current SQL statement.
j) A high number range level may indicate that there is a significant increase for these two BW objects (valid only for BID* and BIM* objects)
SE16 'NRIV'
-> OBJECT = 'BID*' or OBJECT = 'BIM*'
displays all number range objects with number level (NRLEVEL).
Export this output to an Excel document and sort NRLEVEL in descending order. Most candidates usually have a high number range level.
You can determine the corresponding dimension tables by using the table RSDDIMELOC. You can find the InfoObject for SIDs using the table RSDCHABASLOC (the field NUMBRANR contains the last seven digits of the number range object). The procedure is even more effective if you read the table NRIV periodically and you determine the changes using NRLEVEL.
k) Another indicator is if a dimension table or an SID table significantly increases on a regular basis.
How many instances should be buffered?
In the past, a value between 100 and 500 has proved to be efficient. If there is still a high load for these number range objects on the table NRIV, you can increase the value.
Caution:
- Never buffer the number range object of the package dimension table of a data target.
- In addition, never buffer the number range object of the request ID (RSDCHABASLOC-CHABASNM = 0REQUID), generally BIM9999998.
- Ensure that not all dialog processes are occupied permanently
(See Note 708297).
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