Answered Questions

  • Passive Router Transformation

    Router is passive transformation, but one may argue that it is passive because in case if we use default group (only) then there is no change in number of rows. What explanation will you give?

  • What are Dimensions and various types of Dimensions?

    set of level properties that describe a specific aspect of a business, used for analyzing the factual measures of one or more cubes, which use that dimension. Egs. Geography, time, customer and product.

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    ManishTewatia  

    • Member Since Jul-2010 | Jul 22nd, 2010


    What Md.Rehman is trying to say is catagorizing the SCD which are the Slowly Changing Dimensions which are used to maintain historical data.

    Dimension
    :A dimension is an organized hierarchy of categories, known as levels, that describes data in data warehouse fact tables

    The various types of dimensions are :

    1) Shared and Private Dimensions: Describes the basic differences between shared and private dimensions and their uses

    2) Regular Dimensions: Provides information about regular dimensions and their variations

    3) Parent-Child Dimensions: Describes the creation of parent-child dimensions and identifies their advantages and restrictions

    4) Data Mining Dimensions: Describes the creation of data mining dimensions and identifies advantages and restrictions to their use

    5) Virtual Dimensions:Describes the creation of virtual dimensions and their advantages and restrictions

    6) Dependent Dimensions: Describes the creation of dependent dimensions and identifies their advantages and restrictions

    7) Write-Enabled Dimensions: Describes the creation of write-enabled dimensions and identifies their advantages and restrictions

    VIKRAM KUMAR

    • Feb 28th, 2018

    Dimensions are of several types but we use few commonly which are, 1. Confirmed dim. dim. shared by all fact tables. ex- time dim. 2. Slow changing dim. it is of 3 types : SCD1. SCD2, SCD3., 3. Role ...

  • What are Aggregate transformation?

    Aggregator transformation allows you to perform aggregate calculations, such as averages and sums.

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    Answered by: Praveen vasudev

    • Sep 12th, 2005


    Aggregator transform is m uch like the Group by clause in traditional SQL.

    this particular transform is a connected/active transform which can take the incoming data form the mapping pipeline and group them based on the group by ports specified and can caculated aggregate funtions like ( avg, sum, count, stddev....e.tc) for each of those groups.

    From a performanace perspective if your mapping has an AGGREGATOR transform use filters and sorters very early in the pipeline if there is any need for them.

    veepee

    sivakp

    • Mar 13th, 2011

    1. Aggrigator transformation allows to perform aggrigate calculation, such as SUM, MAX, MIN, FIRST, LAST2. Aggrigator transformation allows to perform aggrigate calculation of group.

    shr_4

    • Oct 26th, 2010

    To perform Group by calculations  we use Aggregator Transformation.It perform calculations similar to Expression Transformation.But difference  between both is that Aggregator Transform...