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Staging and Operational Data Store
What are Staging and Operational Data Stores and what is their difference?
Why does one need staging and why does one need ODS? What will happen if they are not there? Who and how is it decided that a staging or ODS is needed? Which comes first staging or ODS?jryan999
- Feb 3rd, 2010
An Operational Data Store (ODS) is a repository of active "operational" data. It's typically used to hold data for a short period (eg. Days or weeks at most), to help the business ...
srilu1234
- Jan 19th, 2010
Stagining and operational data store are different databases.It can be one database aswell to reduce the cost to maitain two databases.Staging is the place where cleansing is done and Operational Stor...
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Suppose your filtering the rows using a filter transformation only the rows meet the condition pass to the target .Tell me where the rows will go that doesnot meet the condition.Thanks in advance
VVM.SP
- Mar 18th, 2008
In Filter Transformation Those row are not meet to the filter condition they are rejected. These rejected rows are appear in $PMBad.Dir
herbert
- Dec 9th, 2006
Yes there is folder or file in informatica which collects this rejected rows, its location is given while installing the s/w
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SCD types
What are the types of slowly changingdimension ?Can you explain please types of slowly changingdimension in detail ?
vijaya
- Aug 29th, 2012
Slowly changing dimensions are 3 types. In scd-1 new data is inserted by deleting old one. so latest information is stored. In scd-2 we can maintain history of data for a particular item. new data is...
bhavikumehta
- Jun 26th, 2012
SCD are of following types: type 1 - updates changes without preserving history type 2 - stores history data by maintaining versions of the updated data type 3 - either stores current and previous ver...
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What is diffrence between SAS tool and other tools.why SAS is so popular?
jag singh
- Jun 12th, 2007
SAS gets adopted by the business groups that do not have a large IT support staff as SAS provides the complete DW environment including ETL and reporting in one easy to manage package. See http://www.dwoptimize.com/2007/02/latest-data-warehouse-industry-trends.html for more comparisons.
mithunmca
- Mar 28th, 2007
Hi The SAS system is an integrated system of software products. The core of the SAS system is Base SAS software. plz visit the following link u will get a idea of w...
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What is data cleaning? How can we do that?
sub_guha
- Jan 25th, 2010
Data cleaning, technically called "Data Cleansing"is a group of methods for making data more reliable and accurate. Usually companies store data in warehouses so they can make meaning out of...
Hakoonamatata
- Jul 9th, 2007
Data cleaning is a self explainatory term. Most of the data warehouses in the world source data from multiple systems - systems that were created long before data warehousing was well understood, and ...
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Difference between Database and Datawarehouse
What are the difference between a database and data warehouse?
gtomar
- Jul 28th, 2008
Database :- database is a collection of related information stored in a structured form in terms of table so that It makes easier insertion, deletion and mainupulation of data. database consist of tab...
ashuboy12345678
- Jul 27th, 2008
Database is a collection of mostly recent data. Where as Datawarehouse consist of historical data the size can vary upto 100 GB or more.Datawarehouse is a combination of datamart used mainly knowledge processing.
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Surrogate Key
Why do we use Surrogate Key?
Rajesh Swarnkar
- Feb 28th, 2012
Usually Surrogate keys are System Generated keys that can be used in place of missing primary key.
sadique_ghitm
- Nov 25th, 2011
A surrogate key in a database is a unique identifier for either an entity in the modeled world or an object in the database. The surrogate key is not derived from application data. A surrogate repres...
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1) Differences between DSS and OLTP.2) Explain Grouped cross tab.3) Define Surrogate key.4) What is IQD file.5) Expalin Reference cursor.
Janaki
- Nov 5th, 2012
3.Surrogate key is a sequencer which is used to uniquely identify a row in a OLAP. This helps in implementing SCD Type 2 in data warehousing.
rj_dwbi
- Apr 2nd, 2012
OLAP:
1). Store historical data of an organization
2). Data is used for BI/ business strategic decision
OLTP
1). Real time transactional data
2). Data is used to have track of transaction details. -
What is the main difference between star and snowflake star schema? Which one is better and why?
bcsandip
- May 25th, 2010
Star Schema: 1. Dimension tables directly connected to Fact Table2. Contain de-normalized data3. Data modifications are very easily4. Highest flexibility5. Best performance6. Takes more memory space t...
geetu rani
- Mar 27th, 2008
STAR SCHEMA HAS fact table linked with dimension table directlywhile in snow flake schema the dimension tables can have futher hierarchies between them .it means in snow flake schema the tables are no...
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1).briefly state different between data ware house & data mart?2).How are u going to consolidate customer infromation in dataware house from the three different back end OLTP applications?3).What is meta data?
surajkm99
- Feb 4th, 2008
1) Difference Between Data Warehouse & Data MartIn Simple Terms Data warehouse : is a SUBJECT - ORIENTED, TIME VARIENT, NON-VOLATILE, INTEGRATED Collection of Data, In Support of Management ...
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Fact and dimensions
Which type of relation between fact and dimension table in star schema and snowflake schema?like one to one or many to many?
naveen
- Dec 16th, 2014
Parent, child relation between fact,dimensions in star schema,snow flake schema
vveeralapati
- Apr 25th, 2013
For one dimension record, you will see many fact records associated.Many to one or one to many relationship is not to be confused with number of records or columns in a table. that has nothing to do with a relation
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What is the difference between database and data warehousing?What is the main advantages of data warehousingWhat is mean by data stageWhat is the famous tools used for data warehousing?What is the architecture of data warehouisng model?
brahmiii
- Feb 28th, 2010
Database is the root of any data releted operations where as datawarehousing is a schema or process how effectively we access or utilize a database. Datawarehousing follows the star schema and snowflake schema as its basic schemas and we two other schemas also which are not much important.
sap_23
- Sep 3rd, 2009
Database: A database is used to record, retrieve, update business transactions which are occurred daily in business life. Data ware House: A data warehouse is used to record historical data, purely for analysis purpose for top management.
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What are the types of dimension tables
nareshcnr
- Nov 6th, 2017
Types of Dimension tables : There are mainly three types of dimension tables available in case of Slowly Changing Dimensions Type 1: Never maintain historical data. only update the existing data. e...
Johnny
- Aug 31st, 2017
The following are the type of dimensions
Slowly changing
Fast Changing
Inferred
Junk
Conformed
Degenerate, and
Static
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