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Time Series Decomposition

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A time series decomposition is a mathematical procedure which transform a original time series into 3 sub-time series. Seasonal: Patterns which repeat with fixed period of time. User page visits to a website increases in the weekends, so a seasonality of 7 days is observed. Trend: Underlying trend of metrics like User page visit count. Random: Residual of time series after allocation into seasonal and trends time series. There are two types of decomposition: Additive and Multiplicative. They have to be chosen correctly for successful decomposition. Additive: The magnitude of seasonality remains constant when time series increases. Time series = Seasonal + Trend + Random Multiplicative: The magnitude of seasonality varies constantly with time series. Time series = Trend * Seasonal *Random
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Using DEFAULT clause for populating Surrogate Keys

In Oracle Database 12 c , a suite of improvements has been implemented around the DEFAULT clause for table columns. A sequence value can now be assigned as the default value for a column. With one simple command, we can remove the need for triggers for populating Surrogate Keys. Creating a DB Trigger: SQL> create or replace   2  trigger TRG_SALES_SURROGATE_KEY   3  before insert on SALES   4  for each row   5  begin   6    :new.SALE_SEQ := SEQ_SALES.nextval;   7  end;   8  /   Trigger created.   Inserting 10 million rows for testing the Insert time.   SQL> insert /*+ APPEND */ into SALES   2  select rownum, ...   3  from   4   ( select 1 from dual connect by level <= 10000 ),   5   ( select 1 from dual connect by level <= 1000 )   6  /   10000000 rows created.   Elapsed: 00:06:3...
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INFA vs. ODI Market Facts

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     I truly believe Informatica is most refined ETL tool in the martket today, but ODI is giving a tough competition with newly added features in 12c, aggressive marketing of ORACLE offering ODI as an embed product within their products.
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XML Analyzer for Informatica PowerCenter

This is a tool that should help to quickly fetch some useful information from Mapping or Workflow XML file and display them in a business-user friendly format. Features: * Ability to download each source-to-target mapping dependency analysis as tab delimited file  (NEW!) * Full Mapplet support  * Reporting transformation ports with default names  * Transformation-level naming convention  * Reporting any implicit datatype conversions  * Reporting Precision / Scale mismatches between linked ports  * List Workflow variables  * List Mapping variables  * Checking for variables unused in mapping  * Added source and target data type to source-to-target column mappings  * Reporting Session level SQL overrides with corresponding Mapping level SQLs  * Listing all source-to-target column mappings * Comparing workflow log file with workflow name * Checking if a session is valid * Checking if a mapping is valid * Tracing level * Overridden ...
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Informatica Message Reference guide.

While using Informatica, may be during installation or coding or data loads we may observed errors n either in logs or in prompt messages.  Similar to ORACLE error codes, Informatica also provides its own set of error messages description out of its identified scope in a documentation. You may download this from below link.  Hope this will be helpful during your work with this tool.  https://community.informatica.com/servlet/JiveServlet/download/116398-40025/IN_951HF2_MessageReference_en.pdf
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The Future for Informatica - Anil Chakravarthy and Charles Race discuss ...

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Relation Database and Warehousing Treasure Trove

http://www.kimballgroup.com/
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