Trouble with star schema
Hi All,
I have a star schema in place with 8 dimension and 1 fact table.
But due to some specific requirement, I need to denormalize the schema. I want to copy all fields from all dimension tables to the fact table.
I know this sounds bad but I have to do it. pls dont ask why..
Now, the same can be done using a materialized view but the problem in MV is there are fields which are present in 2 or more table with the same column name, due to which I cant create a MV.
Is there some other way to achieve this goal.
BRK.
I have too many records which is affecting the performance of the database.
But now its raising performance problems.Your application had a performance problem. Somebody guessed that a star schema would solve the problem. But it hasn't. So now you intend to implement some spavined variant on star schema because somebody has suggested that complete de-normalisation might solve the problem.
Is this a demonstrable fact (you have benchmarks and explain plans to justify it) or just a guess?
I know how difficult this sort of thing can be, because I've been working through some similar scenario for a while now. The important thing is get some decent metrics on your application. Use statspack. Use the wait interface. Find out where your application is spending its time and figure out what you need to do to reduce the waits. Benchmark some alternatives. This may result in you having to re-write your code but at least you'll be doing so in the knowledge
Cheers, APC
Blog : http://radiofreetooting.blogspot.com/
Similar Messages
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Oracle troubles with multiple schemas in same database
We have several different users set up with individual schemas in the
same Oracle database. We run into trouble when more than one user tries
to use Kodo in their local schema. Things go fine for User A, but when
the User B tries to run the schematool on their own Oracle schema, they
get this nonsense:
javax.jdo.JDOFatalDataStoreException: An error occurred while connecting
to the data store.
NestedThrowables:
com.solarmetric.kodo.impl.jdbc.sql.SQLExceptionWrapper: [SQL=SELECT
DISTINCT JDO_SCHEMA_METADATAX.CLASSNAMEX FROM JDO_SCHEMA_METADATAX]
ORA-00942: table or view does not exist
at
com.solarmetric.kodo.impl.jdbc.schema.SchemaTool.<init>(SchemaTool.java:99)
at
com.solarmetric.kodo.impl.jdbc.schema.SchemaTool.main(SchemaTool.java:1114)
at
com.solarmetric.kodo.impl.jdbc.schema.SchemaTool.main(SchemaTool.java:1083)
at
com.solarmetric.kodo.impl.jdbc.schema.SchemaTool.main(SchemaTool.java:1073)
at
com.solarmetric.kodo.impl.jdbc.schema.SchemaTool.main(SchemaTool.java:1064)
If the User A drops all the tables from their schema, then things go
fine for User B ... but then User A will have the same problem when they
try to run the schematool.
It is our suspicion that Kodo is actually selecting the metadata all of
the tables in **everybody's** schemas, and thus erroneously thinking
that jdo_schema_medatax already exists. It really ought to restrict
itself to the schema it's actually connected to.
If our theory is correct, it would explain why Kodo is so incredibly,
horribly, painfully slow to connect to our Oracle database -- we have
dozens of schemas in there, many of which have hundreds of tables.
Is 2.3.0 addressing this problem?
PaulPaul,
Are you using the 'schema-name' system preference setting for each user?
Oracle's mechanism for selecting database metadata requires that the
appropriate schema name be explicitly when more than one schemas are used.
See the database setup section of our documentation for more information.
-Patrick
On 7/3/02 3:50 PM, "Paul Cantrell" <[email protected]> wrote:
We have several different users set up with individual schemas in the
same Oracle database. We run into trouble when more than one user tries
to use Kodo in their local schema. Things go fine for User A, but when
the User B tries to run the schematool on their own Oracle schema, they
get this nonsense:
javax.jdo.JDOFatalDataStoreException: An error occurred while connecting
to the data store.
NestedThrowables:
com.solarmetric.kodo.impl.jdbc.sql.SQLExceptionWrapper: [SQL=SELECT
DISTINCT JDO_SCHEMA_METADATAX.CLASSNAMEX FROM JDO_SCHEMA_METADATAX]
ORA-00942: table or view does not exist
at
com.solarmetric.kodo.impl.jdbc.schema.SchemaTool.<init>(SchemaTool.java:99)
at
com.solarmetric.kodo.impl.jdbc.schema.SchemaTool.main(SchemaTool.java:1114)
at
com.solarmetric.kodo.impl.jdbc.schema.SchemaTool.main(SchemaTool.java:1083)
at
com.solarmetric.kodo.impl.jdbc.schema.SchemaTool.main(SchemaTool.java:1073)
at
com.solarmetric.kodo.impl.jdbc.schema.SchemaTool.main(SchemaTool.java:1064)
If the User A drops all the tables from their schema, then things go
fine for User B ... but then User A will have the same problem when they
try to run the schematool.
It is our suspicion that Kodo is actually selecting the metadata all of
the tables in **everybody's** schemas, and thus erroneously thinking
that jdo_schema_medatax already exists. It really ought to restrict
itself to the schema it's actually connected to.
If our theory is correct, it would explain why Kodo is so incredibly,
horribly, painfully slow to connect to our Oracle database -- we have
dozens of schemas in there, many of which have hundreds of tables.
Is 2.3.0 addressing this problem?
Paul
Patrick Linskey [email protected]
SolarMetric Inc. http://www.solarmetric.com -
Trouble with Star Chart(s)
I have loaded both the Google Sky Map and Star Chart. I've used both of these successfully with a Thunderbolt and a Droid (One) - but with the Razr the azimuth does not change when the phone is re-oriented. Elevation appears to work, but the azimuth moves randomly when the phone is turned from - say - north to east. It would appear that the compass orientation function is off.
Has anyone else had this problem? Thanks.I'm having the exact same issues...tried multiple apps, uninstalling and reinstalling each of them, seeing they were the problem, but when they all react the same way it can only be the phone. The most ironic thing is that "space junk" actually appears to show my phone oriented in the correct wa y(has a separate view option for this) that makes the app appear that it should work properly and moves correctly according to the satellites. Yet as you rotate from north to west/east/etc...the phone lags then all of the sudden skips almost 180 degrees. Would love for them to fix this bug, works fine on all my other friends' droid phones, just not this one.
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Star schema or Snowflake schema
Hi Gurus,
I have following dimensions and fact table. let me know can I go ahead with star schema and snowflake schema while building the cube.
1. Country's table
2. workgroup table --> each country have N number of work groups
3. user table---> each workgroup have N number of users.
4. time table.
5. fact table.This is a similar thread that discusses on the design approach of star vs normalized tables
https://social.technet.microsoft.com/Forums/sqlserver/en-US/7bf4ca30-a1bc-415d-97e6-ce0ac3137b53/normalized-3nf-vs-denormalizedstar-schema-data-warehouse-?forum=sqldatawarehousing
In my experience majority of cases I've some across is also star schema for data marts where tables will be more denormalized rather than applying priciples of normalization. And I believe so far as its through SSAS cubes that you exposes the OLAP model
it would be much easier to implement relationships using a denormalised approach.
What you may do is to have a normalised datawarehouse if you want and then built the datamarts over it using denormalised tables (star schema) for the cube.
Please Mark This As Answer if it solved your issue
Please Vote This As Helpful if it helps to solve your issue
Visakh
My Wiki User Page
My MSDN Page
My Personal Blog
My Facebook Page -
Snowflake/Star Schema in OBIEE
Hi Gurus,
I would be very glad if you can help me to resolve this problem.
Before posting, I searched the forum there are similar queries(Circular Join) but I do not get the solution.
I have fact and dimension tables builded with star schema which I do not have any problem. But there is a fact table which has dimension to dimension relation between them.
When I tried to connect them which I explained in below I am getting error(Circular join problem) or If I fix the error, In Obiee analysis I am getting another error which says there is no fact table between tables. Let me explain the situation;
I have 4 dimensions table and a fact table;
connection between them;
Sales Dim(1) ---> Fact.A(N)
Date Dim(1) ---> Fact.A(N)
Customer Dim(1) ---->Fact.A(N)
Sales Channels Dim(1) --->Sales Dim(N)
Date Dim(1)---> Sales Dim(N)
Date Dim(1) ---->SalesChannel(N)
I can see that there are bunch of circular join in here :(. I did not understand to use Alias to resolve this problem.
For instance; Dim A--->Fact AC
Dim B --->Fact AC
Dim A---> Dim B
If I create a Alias for Dim A, I can resolve the problem but which of them should I drag to Presentation Layer(at the end both of them same but Dim A used by other fact tables too). If I drag to Dim A nothing will be change or I am totally lost:(
If you do not understand the question I will try to be more clear.
I would be very happy if you can help me.
Thanks in advance.
M.SHi M.S,
If I got your issue correctly, then the issue is the join between the 'Date Dim' -> 'Sales Dim' and 'Date Dim' -> 'Channels Dim'. I was just trying to understand the model here, and thinking why do you need a join between these dimensions.
Anyway, a report with Sales and Date dimension can always be resolved through the Fact table. However, if you still want all combinations across this dimension, you can still use a implicit column methodology for this issue. you might want to refer to venkat's blog on this approach here.http://www.rittmanmead.com/2009/08/oracle-bi-ee-10-1-3-4-1-reporting-on-non-transactional-dimension-values-equivalence-of-outer-joins/
Hope this helps.
Thank you,
Dhar -
Need help with an extended star schema.
I have the following data in spreadsheet form and I need to transpose this into an extended star schema in order to prdouce my characteristics and key figures, however I'm having a little trouble understanding where to include the Product Group in the star schema and also what to do with the Sales Doc (Invoice Number) in the sales information spreadsheet.
I need to summarise the data into the following also:
1. Total quantity and revenue for each Channel and product group
2. Total quantity and revenue for each Channel and product group (July 2009 to September 2009)
3. Total Quantity and Revenue for iphone sales
So my question in short is what would the star schema look like? I'm hoping somebody can help me over this hurdle.
The following are the details from the spreadsheet:
Product Details (Attributes)
File Name: Product_Details.csv
Structure FieldName Length Description
ProdID 5 Uniquely identifies a product
PG_Group 20 Identifies products in specific groups (Navigational field)
Sample Data
ProdID,PG_Group
PDS01,COMPUTER
PDS02,COMPUTER
PDS03,COMPUTER
PDS04,ACCESSORIES
PDS05,ACCESSORIES
PDS06,ACCESSORIES
PDS07,ACCESSORIES
PDS08,HARDWARE
Product Description (Text)
File Name: Product.csv
Structure FieldName Length Description
ProdID 5 Uniquely identifies a product
Prod_Desc Medium Text Represents the product description
(Navigational field)
Language 2 Represents the language descriptor
Sample Data
ProdID,Prod_Desc,Language
PDS01,Notebook Speedy I,EN
PDS02,Notebook Speedy II,EN
PDS03,PC Thinkbox I,EN
PDS04,USB Adaptor,EN
PDS05,iPhones PX2,EN
PDS06, Stereo Kit,EN
PDS07,Camera Connector,EN
PDS08,USB Storage,EN
Transactional Data
Sales information
File Name: Sales.txt
Structure FieldName Length Description
Product 5 Uniquely identifies a product
Sales Doc 4 Sales Document number (Invoice Number)
Calendar Year 8 YYYYMMDD format
Channel 1 Represents the distribution channel the product was sold by
Quantity 4 Numeric value indicating the number of each product sold on a specific sales document
Unit 2 Refers the unit specified by the quantity
Revenue 8 Refers the sales amount of a specific product on a specific sales document
Currency 3 Relates the revenue currency type
Sample Data
Product;Sales Doc ,Calendar Day,Channel,Quantity,Unit;Revenue,Currency
ZD_PROD,0DOC_NUMBER,0CALDAY,ZD_CHAN,ZD_QTY,0UNIT,ZD_REV,0CURRENCY
PDS07,7389,20090705,A,95,EA,151905,USD
PDS08,7389,20090705,A,115,EA,264385,USD
PDS02,7473,20090706,B,55,EA,3580445,USD
PDS01,7472,20090706,C,110,EA,604989,USD
PDS02,7472,20090706,C,43,EA,2799257,USD
PDS03,7472,20090706,C,75,EA,4507425,USD
PDS04,7472,20090706,A,339,EA,301032,USD
PDS06,7472,20090706,A,120,EA,47976,USD
PDS01,7473,20090718,D,55,EA,3024945,USD
PDS02,6845,20090806,B,30,EA,195297,USD
PDS07,6877,20090807,C,800,EA,12792,USD
PDS08,6877,20090807,C,250,EA,57475,USD
PDS03,6912,20090812,C,250,EA,1502475,USD
PDS04,6900,20090812,B,70,EA,6216,USD
PDS01,6899,20090812,C,12,EA,659988,USD
PDS04,6899,20090812,D,55,EA,4884,USD
PDS04,7479,20090815,C,80,EA,7104,USD
PDS05,7479,20090815,C,300,EA,70497,USD
PDS05,6809,20090818,A,1000,EA,234990,USD
PDS06,6809,20090818,A,130,EA,51974,USD
PDS03,6831,20090822,C,15,EA,901485,USD
PDS04,6831,20090822,C,500,EA,4440,USD
PDS03,6830,20090822,C,125,EA,7512375,USD
PDS06,6830,20090822,C,400,EA,15992,USD
PDS04,6841,20090825,C,53,EA,47064,USD
PDS05,6841,20090825,C,350,EA,822465,USD
Distribution Channel
Channel (text)
File Name: Channel.csv
Structure FieldName Length Description
ChanID 1 Uniquely identifies a specific distribution channel
Chan_Desc Medium
Text Full name of each distribution channel
(Navigational field)
Sample Data
ChanID, Chan_Desc
A,Phone
B,Fax
C,Internet
D,Other
Star Schema Model:Potentially the issue may be the combination of actual distance and the presence of any Wi-Fi interference at the location of the AirPort Express that may be the culprit here. The bottom line is you would want the Express to be within a 25+ dB range of the Extreme to be sure that it can consistently stay connected to it.
For more details on proper base station placement, check out the following AirPort User tip. Please post back your results. -
Error with creating star schema using HsvStarSchemaACM
Hi,
I am trying to create a star schema using the API HsvStarSchemaACM. But when calling the create function of API, i get the below exception. Exception from HRESULT: 0x80040251 (A general error occurred while trying to obtain a database Reader/Writer lock). Is this something to do with the parameters passed and its connections(connection works fine and createstarschema is running thru workspace).
Any solutions to this is more welcome.
Thanks,
LoguCan you provide details on HsvStarSchemaACM API? How is it related to ODI?
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What is star schema - pls explain with example
Hai.
what is star schema - pls explain with example
thanks in advance
GiriHi Giri,
SAP's BIW employs extended star schama
The extended star schema consists of a fact table (in two parts, E and F - f is the inbound table, E long-term storage). Dimension tables are connected to the fact tables via the DIMID(dimension id) which is a generated value and is stored in both dimension and fact tables. In addition, the dimension tables are connected to tables which hold master data values (or bind the dimension table to tables that hold the values), such as S tables, P, Q, X, Y. These dimension tables hold SIDs, again generated keys which relate values in the dimension table (the DIMIDs) with master data values. Thus, at the time of the query, join operations ensure that the master data values can be merged with the key figure values stored in the fact tables.
Truthfully, one does not need to understand this schema extensively in order to model in BI in SAP NetWeaver. It helps to understand master data, navigational attributes, etc. Otherwise, simply model the key figures in the fact table and the characteristics into dimensions and you're good - the application generates the star schema for you - you don't have to specify it.
See the transaction "LISTSCHEMA" which will show you the relationship between the F fact table and the other tables of the cube's star schema.
Also follow the link for more info:
http://help.sap.com/saphelp_nw04/helpdata/en/4c/89dc37c7f2d67ae10000009b38f889/content.htm
Thanks for any points you assign.
Regards -
Resolving loops in a star schema with 5 fact tables and 6 dimension tables
Hello
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.
I did adopt the best practices, and as recommended in the book, I tried to resolve them using Context, as it is the recommended option to Alias in a star schema setting. The contexts are resolved, but I still have loops. I also cleared the Multiple SQL Statement for each context option, but no luck. I need to get this resoved ASAPHi Patil,
It is not clear what exactly is the problem. As a starting point you could set the context up so that it only covers the joins from fact to dimension.
Fact A, joins Dim 1, Dim 2, Dim 3, and Dim 4
Fact B, joins Dim 1, Dim 2, Dim 3, Dim 4 and Dim 5
Fact C, joins Dim 1, Dim 2, Dim 3, Dim 4 and Dim 6
Fact D, joins Dim 1, Dim 2, Dim 3, Dim 4 and Dim 7
Fact E, joins Dim 1, Dim 2, Dim 4 and Dim 6
If each of these are contexts are done and just cover the joins from fact to dim then you should be not get loops.
If you could lay out your joins like above then it may be possible to specify the contexts/aliases that should work.
Regards
Alan -
Relational Star Schema with oWB 10g
Hi,
It is an interesting forum. I like to explore the different approached to build ETL using OWB to load Star Schema built around Oracle 10g relational structures.
How do we take advantage of additional features of Oracle DB 10g and OWB 10gR2?
What features does help? Which one should stay away from?
Thanks in advance.
RamHi ,
You can use Oracle SQL Developer Data Modeler .
SQL Developer Data Modeler provides a full spectrum of data and database modeling tools and utilities, including modeling for Entity Relationship Diagrams (ERD), Relational (database design), Data Type and Multi-dimensional modeling, full forward and reverse engineering and DDL code generation. The Data Modeler imports from and exports to a variety of sources and targets, provides a variety of formatting options and validates the models through a predefined set of design rules.
Oracle SQL Developer Data Modeler can connect to any supported Oracle Database and is platform independent
http://www.oracle.com/technology/products/database/datamodeler/index.html
Thanks,
Sutirtha -
Star Schemas with designer 6.0
How can I easily create star schemas for a Datawarehouse in Designer6? Where can I still find documentation for such release?
MauroMauro,
You should be able to create start schemas - search in the online help for all references to data warehousing
and star schemas. There should be a few topics.
Regards,
Dominic
Designer Product Management
Oracle Corp -
Hi Guys,
I have designed a Star schema for one of my datamart and my client is after me suggesting that over that I should create a MV to provide a consolidated view. I am trying to convience my client not to do so with the points as below:
1. As we have created a Star Schema in the database we should take advantages of the same and should avoid creating another layer of reporting which in future will increase the complexity of the queries while expanding the functionality of the mart.
2. We have to create a complete refresh MV and during refresh data will not be available for reporting to users and the duration will increase over the period of time once the data increases
3. As MV are a table on a disk using a MV in this case will consume the tablespace which will increase over the period of time.
Please can you experts suggest of any more points or additions. We are using SAP BO as a reporting tool in our organization wherein a Universe can be created easily for reporting.
Cheers,
ShazI have designed a Star schema for one of my datamart and my client is after me suggesting that over that I should create a MV to provide a consolidated view. I am trying to convience my client not to do so with the points as below:You are convincing them to NOT do one of the the things materialized views were originally introduced to provide?
I'm purposely going all the way back to 8i documentation here to emphasize the point.
http://docs.oracle.com/cd/A87860_01/doc/server.817/a76994/qr.htm#35520
" Overview of Query RewriteOne of the major benefits of creating and maintaining materialized views is the ability to take advantage of query rewrite, which transforms a SQL statement expressed in terms of tables or views into a statement accessing one or more materialized views that are defined on the detail tables. The transformation is transparent to the end user or application, requiring no intervention and no reference to the materialized view in the SQL statement. Because query rewrite is transparent, materialized views can be added or dropped just like indexes without invalidating the SQL in the application code. "
>
The theory behind query rewrite is this: have them build their queries based on your star schema (or you a build a traditional view that does that), then build a materialized view that mirrors the query/view. If the materialized view is refreshing or not up-to-date, their queries will run (more slowly) against the star schema. If it is up-to-date it will be used instead, providing faster results.
But before you go to that trouble: they are asking for a consolidated view (presumably something easier to query - common in data warehousing). You can create a view to provide this. If that view is not fast enough for their performance requirements, materialize it. Yes, the materialized view uses space, but that space is the price you pay for meeting the performance requirement. -
Using two facts of two different star schemas and conformed dimensions
Hi,
I've been working as developer and database designer for years and I'm new to Business Objects. Some people says you can not use two facts of two different star schemas in the same query because of conformed dimensions and loop problems in BO.
For example I have a CUSTOMER_SALE_fACT table containing customer_id and date_id as FK, and some other business metrics about sales. And there is another fact table CUSTOMER_CAMPAIGN_FACT which also contains customer_id and date_id as FK, and some other business metrics about customer campaigns. SO I have two stars like below:
DIM_TIME -- SALE_FACT -- DIM_CUSTOMER
DIM_TIME -- CAMPAIGN_FACT -- DIM_CUSTOMER
Business metrics are loaded into fact tables and facts can be used together along conformed dimensions . This is one of the fundamentals of the dimensional modeling. Is it really impossible to use SALE_FACT and CAMPAIGN_FACT together? If the answer is No, what is the solution?
Saying "you cannot do that because of loops" is very interesting.
Thank you..When you join two facts together with a common dimension you have created what is called a "chasm trap" which leads to invalid results because of the way SQL is processed. The query rows are first retrieved and then aggregated. Since sales fact and campaign fact have no direct relationship, the rows coming from either side can end up as a product join.
Suppose a customer has 3 sales fact rows and 2 campaign fact rows. The result set will have six rows before any aggregation is performed. That would mean that sales measures are doubled and campaign measures are tripled.
You can report on them together, using multiple SQL passes, but you can't query them together. Does that distinction make sense? -
Injecting data into a star schema from a flat staging table
I'm trying to work out a best approach for getting data from a very flat staging table and then loading it into a star schema - I take a row from a table with for example 50 different attributes about a person and then load these into a host of different tables, including linking tables.
One of the attibutes in the staging table will be an instruction to either insert the person and their new data, or update a person and some component of their data or maybe even to terminate a persons records.
I plan to use PL/SQL but I'm not sure on the best approach.
The staging table data will be loaded every 10 minutes and will contain about 300 updates.
I'm not sure if I should just select the staging records into a cursor then insert into the various tables?
Has anyone got any working examples based on a similar experience?
I can provide a working example if required.The database has some elements that make SQL a tad harder to use?
For example:
CREATE TABLE staging
(person_id NUMBER(10) NOT NULL ,
title VARCHAR2(15) NULL ,
initials VARCHAR2(5) NULL ,
forename VARCHAR2(30) NULL ,
middle_name VARCHAR2(30) NULL ,
surname VARCHAR2(50) NULL,
dial_number VARCHAR2(30) NULL,
Is_Contactable CHAR(1) NULL);
INSERT INTO staging
(person_id, title, initials, forename, middle_name, surname, dial_number)
VALUES ('12345', 'Mr', 'NULL', 'Joe', NULL, 'Bloggs', '0117512345','Y')
CREATE TABLE person
(person_id NUMBER(10) NOT NULL ,
title VARCHAR2(15) NULL ,
initials VARCHAR2(5) NULL ,
forename VARCHAR2(30) NULL ,
middle_name VARCHAR2(30) NULL ,
surname VARCHAR2(50) NULL);
CREATE UNIQUE INDEX XPKPerson ON Person
(Person_ID ASC);
ALTER TABLE Person
ADD CONSTRAINT XPKPerson PRIMARY KEY (Person_ID);
CREATE TABLE person_comm
(person_id NUMBER(10) NOT NULL ,
comm_type_id NUMBER(10) NOT NULL ,
comm_id NUMBER(10) NOT NULL );
CREATE UNIQUE INDEX XPKPerson_Comm ON Person_Comm
(Person_ID ASC,Comm_Type_ID ASC,Comm_ID ASC);
ALTER TABLE Person_Comm
ADD CONSTRAINT XPKPerson_Comm PRIMARY KEY (Person_ID,Comm_Type_ID,Comm_ID);
CREATE TABLE person_comm_preference
(person_id NUMBER(10) NOT NULL ,
comm_type_id NUMBER(10) NOT NULL
Is_Contactable CHAR(1) NULL);
CREATE UNIQUE INDEX XPKPerson_Comm_Preference ON Person_Comm_Preference
(Person_ID ASC,Comm_Type_ID ASC);
ALTER TABLE Person_Comm_Preference
ADD CONSTRAINT XPKPerson_Comm_Preference PRIMARY KEY (Person_ID,Comm_Type_ID);
CREATE TABLE comm_type
comm_type_id NUMBER(10) NOT NULL ,
NAME VARCHAR2(25) NULL ,
description VARCHAR2(100) NULL ,
comm_table_name VARCHAR2(50) NULL);
CREATE UNIQUE INDEX XPKComm_Type ON Comm_Type
(Comm_Type_ID ASC);
ALTER TABLE Comm_Type
ADD CONSTRAINT XPKComm_Type PRIMARY KEY (Comm_Type_ID);
insert into comm_type (comm_type_id, NAME, description, comm_table_name) values ('23456','HOME PHONE','Home Phone Number','PHONE');
CREATE TABLE phone
(phone_id NUMBER(10) NOT NULL ,
dial_number VARCHAR2(30) NULL);
Take the record from Staging then update:
'person'
'Person_Comm_Preference' Based on a comm_type of 'HOME_PHONE'
'person_comm' Derived from 'Person' and 'Person_Comm_Preference'
Then update 'Phone' with the number based on a link derived from 'Phone' which is made up of Person_Comm Primary_Key where 'Comm_ID' (part of that composite key)
relates to the Phone table Primary_Key which is Phone_ID.
Does you head hurt as much as mine? -
Hi Experts,
Please tell me the places in OBIEE 11G where i can design the start schema.is it only in Physical Layer or In BBM too?
Thanks-BhaskarFinal point, for performance reasons you should also try to model data into star schema in the physical layer.
If the data is modelled as a true star then there are database features which optimise query performance. These features are set by a DBA when the Warehouse is configured (e.g. enable_star_transformations). The results with this parameter on/off can be staggering (query time reduced from minutes to seconds), showing the power of star schema.
When snowflakes occur, these performance features will not work as designed, and performance will be degraded. There are certain criteria that have to be met by the data e.g. bitmap indices on all of the foreign key columns in the fact.
Please mark if helpful / correct,
Andy
www.project.eu.com
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Trying to get Excel talk to ABAP RFC Web Service. - Excel - 2007 ( Since it is Excel 2007, I didn't had to add any Office Web Services Toolkit or any add on ) - ECC 6.0 Excel (VB) not throwing any error, but is not giving any output ( expecting a t
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Hello, I want to create a form in the portal. I go to PORTLET BUILDERS --> Form Portlet --> define --> Form based on table or view ....--> Finish. But when I finish the Wizard no form appears in the region. What can I do? Thank you for helping.