Star schema cannot be mapped to multiple tables

Hello!
I am mapping dimension in AWM.
When I am drawing lines from the source columns to the target objects "Member". I get the message "star schema cannot be mapped to multiple tables". Sometimes I can workaround the problem by drawing the lines in a different order. But this dose not always work
I have a dimension that have several levels and hierarchy and I always get the message "star schema cannot be mapped to multiple tables" no matter in witch order I draw the lines to "Member".
Why do I get this message and how do I do to solve the problem?
Best regards,
Tina N Mörnstam

Hi Tina:
Is your dimension snowflaked? Are you mapping from more than one source table to the target dimension? Is the hierarchy formed over different tables?
Hazbleydi C. Verástegui

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Is it possible to map several tables with only one BMP?
if so please send me an example (class bean)
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hi,
yes, entity bean can be mapped to multiple tables provided it is bean managed entity bean.
since, container cannot prepare complex quries so that we need to rely on bean managed persistance.
Ex : Assume you have two table like X, Y
where X table having fields (int x primarykey, varchar str) and Y table having fields (varchar name primarykey, int y).
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public class BeanPriamkey implements java.io.Serializable
protected int x;
protected String name;
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public BeanPramkey(int x,String str)
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public int hashCode()
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Hi,
I need to store the rdf schema in one table and rdf instance data in another table.
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Hi,
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---
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Star schema design

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"Reverse Star schema" to star schema

Hey
This is my first post and I´m working with OWB for abou 4 Months now.
My problem:
I am working with a cube but instead of a real star schema I always get a model like this:
a fact in the fact table of my cube matches to multiple records in the dimensions. (1 to n)
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See if this helps,
http://docs.oracle.com/cd/E14571_01/bi.1111/e10540/busmodlayer.htm#BGBJGJIB
http://kimballgroup.forumotion.net/t1356-weighting-factor-in-bridge-table

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Hi devs,
I'm in the process of creating OLAP dimensions using AWM 10.2.0.30A on 10gR2 database, and have successfully created some flat (no levels) dimensions. Now I have to create another dimension, which based on existing model, has parent and child in same dimension table at database end.
When I first attempt to do this using the default "Star Schema" setting for type of dimension table in the mapping section, I get the below error:
oracle.AWXML.AWException: Action BUILDDATABASE failed on object TA_DMT_OWNER.GLA_MP
at oracle.AWAction.BuildDatabase.Execute(BuildDatabase.java:737)
at oracle.olap.awm.wizard.awbuild.BuildWizardHelper$1.construct(BuildWizardHelper.java:184)
at oracle.olap.awm.ui.SwingWorker$2.run(SwingWorker.java:109)
at java.lang.Thread.run(Thread.java:534)
Caused by: oracle.AWXML.AWException: ***Error Occured in BUILD_DRIVER: In __XML_SEQUENTIAL_LOADER: In __XML_LOAD_HIERS: In __XML_SET_GID_FREL: One or more loops have been detected in relationship GLA_MP!PROD_PARENTREL over GLA_MP!PROD. The 1 items involved are TD.
at oracle.AWAction.BuildDatabase.Execute(BuildDatabase.java:604)
... 3 more
I've tried changing the type to "Snowflake" but get the same error. Do you have suggestions as to how to best handle these scenarios?
**Little more background to the data. We DO have surrogate keys in table as well, which is used in fact table. If I do not use the "use natural keys from data source" and use "generate surrogate keys in AW" option, dimension is built successfully. So my follow-up question is, when I build cube will AW know to link the dimension correctly from fact based on surrogates generated by AWM even though those surrogate keys do not physically exist in fact?
Edited by: user8659932 on Oct 30, 2009 7:58 AM

When I first attempt to do this using the default "Star Schema" setting for type of dimension table in the mapping section, I get the below error:
oracle.AWXML.AWException: Action BUILDDATABASE failed on object TA_DMT_OWNER.GLA_MP
at oracle.AWAction.BuildDatabase.Execute(BuildDatabase.java:737)
at oracle.olap.awm.wizard.awbuild.BuildWizardHelper$1.construct(BuildWizardHelper.java:184)
at oracle.olap.awm.ui.SwingWorker$2.run(SwingWorker.java:109)
at java.lang.Thread.run(Thread.java:534)
Caused by: oracle.AWXML.AWException: ***Error Occured in BUILD_DRIVER: In __XML_SEQUENTIAL_LOADER: In __XML_LOAD_HIERS: In __XML_SET_GID_FREL: One or more loops have been detected in relationship GLA_MP!PROD_PARENTREL over GLA_MP!PROD. The 1 items involved are TD.
at oracle.AWAction.BuildDatabase.Execute(BuildDatabase.java:604)This error comes when you have a member rolloing to a different via two different path. If you use surrogate key then as you said the error is gone.
**Little more background to the data. We DO have surrogate keys in table as well, which is used in fact table. If I do not use the "use natural keys from data >source" and use "generate surrogate keys in AW" option, dimension is built successfully. It appended the some text to the value.
So my follow-up question is, when I build cube will AW know to link >the dimension correctly from fact based on surrogates generated by AWM even though >those surrogate keys do not physically exist in fact?Yes it do. You needn't to fabricate that kind of fact data.
You can check this link -> http://www.oracle.com/technology/products/bi/olap/index.html
Thanks,
Brijesh
Edited by: Brijesh Gaur on Oct 30, 2009 9:08 PM

Star schema of Datawarehouse

Hi,
I'm working with BI Apps (OBIEE) uploaded on PeopleSoft HCM 9.1 source system. I'm using pre built ETL task to load the pre designed Datawarehouse.I want to know where can I found the Datawarehouse star schema description?

What you are looking for the DMR (Datawarehouse Model Reference) Doc. I believe they have this on Metalink for the BI Apps releases. This provides the physcial star schemas and details on the DW tables. Here is the metalink note:
Oracle Business Analytics Warehouse Data Model Reference Version 7.9.6, 7.9.6.1 and 7.9.6.2 [ID 819373.1
If this was helpful, please mark the response as correct.

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I have a star schema, ie 5 FACT tables and 7 dimension tables, All fact tables share the same dimension tables, some FACT tables share 3 dimesnsions, while other share 5 dimensions.
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The database has some elements that make SQL a tad harder to use?
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forename VARCHAR2(30) NULL ,
middle_name VARCHAR2(30) NULL ,
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forename VARCHAR2(30) NULL ,
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Star schema without a fact table?

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I'm preparing my warehouse for using with Discoverer and my question is about the star schema.
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Hi,
Is a star schema directly associated with data warehouse?Not really, a star schema is just one where there is one large fact table joined to many smaller dimension tables using key fields. You usually see this in data warehouses.
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Hi Sion,
After I make the tables incompatible with the dimension objects on different levels, the measure can point to the right table if my query only include Store and Product or only include Region and Department. But in some scenario, the business could ask to include both Store and Region or Item and Department in same query. The current approach doesn't work on this further request. In our database, we have store table including Region with other higher level organization information, Product table including Department with other higher level product information, and we also have separated Region table and Department table. Could we make the objects more flexible u2013 query will be against aggregation sales table if dimension objects in query are only on higher level and will against detail sales table if some of dimension objects are on high level and some on low level?
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Hi George,
If you are working with 11g - did you install all the latest patches? I strongly recommend applying all available patches when working with 11g. All the information you need is here - http://www.oracle.com/technology/products/bi/olap/collateral/olap_certification.html
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OLAP Blog: http://oracleOLAP.blogspot.com
OLAP Wiki: http://wiki.oracle.com/page/Oracle+OLAP+Option
OLAP on OTN: http://www.oracle.com/technology/products/bi/olap/index.html
DW on OTN : http://www.oracle.com/technology/products/bi/db/11g/index.html

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Hi i was trying to prepare a very small demo for an OLAP system. Anyways I have a simple transaction database for a supposed Book Store anyways the database has the following 3 tables :
Table No:1
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This Table contains the following columns:
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Table No:2
Table Name:Customer Table
This Table contains the following columns:
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Table Name:BOOKS Table
This Table contains the following columns:
BOOK Name | Book Purchase ID | GENRE
so the above is my transactional database.. LEt me know if i am missing any other detail. Anyways now i want to convert the above to start schema ?? How would i acccomplish that .. I tried to read a couple of tutorials but i was a bit confused... so if you guys could assist me on this i would be really thnakfull.

David_Aldridge wrote:
thinking in general about this, it sounds like what you need is a set of four tables:
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Use synthetic keys for all but the Dim_Date.Okay i kind of got lost on the way here is wht i know so far regarding the star schema
"A star schema consists of fact tables and dimension tables. Fact tables contain the quantitative or factual data about a business--the information being queried. This information is often numerical, additive measurements and can consist of many columns and millions or billions of rows. Dimension tables are usually smaller and hold descriptive data that reflects the dimensions, or attributes, of a business. SQL queries then use joins between fact and dimension tables and constraints on the data to return selected information."
so from your explaination there are going to be 3 dimension tables
Dim_Cust (Details about the customers) (Customer_ID,Cell No,Address)
Dim_Book(Details about the Books) (Book Name ,ID,Genre)
Dates (I am confused about the dates part)
Fct_Book_Sales (Confused about this part also)
and one last thing What would the fact table look like ??

Star schema cannot be mapped to multiple tables

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