Logical vs. Physical Partitioning

Hi,
In a discussion of logical partition the author pointed out that
“… if a query that needs data from all 5 years would then automatically (you can control this) be split into 5 separate queries, one against each cube, running at the same time. The system automatically merges the results from the 5 queries into a single result set.”
1. Can you direct me on how to “control this” as the author indicated?
2. Also, the author noted that
“… Physical Partitioning - I believe only Oracle and Informix currently support Range partitioning. …”
a) Does it mean that BW does not use physical partitioning?
b) Where do we indicate physical or logical partitioning as an option in BW?
c) Or, when we talk about dimension table, etc. is there always an underlining database such as Oravle, Infomix, etc in BW? If so, what does BW use?
3. For physical partitions, I read that the cube needs to be empty before it can be partitioned. What about logical partition?
4. Finally, what are the underlying criteria to decide on logical or physical partitioning or both
Thanks

. Can you direct me on how to “control this” as the author indicated?
You make this setting RSRT.
2. Also, the author noted that
“… Physical Partitioning - I believe only Oracle and Informix currently support Range partitioning. …”
DB2 also support partiioning. Also the current relese of SQL server support partitioning.
b) Where do we indicate physical or logical partitioning as an option in BW?
Physical parittions are set up in the cube change option. When you are in  the cube change mode, on the themenu, chose extras - performance / DB parameters - parttitios.
Now a screen will pop giving the time characteristics in the cube and choose the characteristic (s) that you wish to chose and confirm the entries - then you will get another small pop up where you set the no of parittions.
Also, pl note that you can partition only on fiscalyear and fiscal period and not on other time characteritsitcs.
Logical partitions: Logical paritions are nothinb but spilting the cube into numerous cubes of smaller sizes. You combine all these cubes by means of multi provider. For example, if you have 1000 cost centers , you may want to split into cubes based on the cost cenree numbers and combine them into a multi provider.
No more setting is required.
c) Or, when we talk about dimension table, etc. is there always an underlining database such as Oravle, Infomix, etc in BW? If so, what does BW use?
Dimension tables / fact tables/ ODS tables /master data tables are all database tables. Which ever database you use and when yu activate these objects, the tables are created in the underlying database.
3. For physical partitions, I read that the cube needs to be empty before it can be partitioned. What about logical partition?
Logical partiton can be done any time.
4. Finally, what are the underlying criteria to decide on logical or physical partitioning or both
The underlying criteria is facotrs such as :
(a) the no of years of history tou wish to view in reports.
(b) te no ofyears you will hold the data in BW before archiving.
(c) othe performance matters related tro sizing.
Ravi Thothadri

Similar Messages

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    What is the diff between the logical and physical partitions. The partitions that we do on a cube based on 0calmonth / 0fiscyear is that logical or physical.
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    https://www.sdn.sap.com/irj/servlet/prt/portal/prtroot/docs/library/uuid/ce7fb368-0601-0010-64ba-fadc985a1f94
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    Hash Partitioning: IBM DB2/UDB
    Database (or Physical) Partitioning
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    -Read smaller sets of data Fast
    -Deletion of partitions (DROP PARTITION instead DELETE FROM WHERE)
    *Automatically Partitioned Database Tables (for Range Partitioning)
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    -Change Log: similar to PSA table
    *User Defined Partitioning Criteria (for Range Partitioning)
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    MultiProvider (or Logical)
    -Partitioning Possible partitioning criteria: year, plan/actual, regions, business area
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  • Physical partitioning have anything to do with where data is on the disk?

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    Edited by: Benson Wong on Mar 4, 2010 6:38 PM
    Edited by: Benson Wong on Mar 4, 2010 6:42 PM
    Edited by: Benson Wong on Mar 4, 2010 6:42 PM

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    hi
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