IBM InfoSphere DataStage



IBM InfoSphere DataStage is an ETL tool and part of the IBM Information Platforms Solutions suite and IBM InfoSphere. It uses a graphical notation to construct data integration solutions and is available in various versions such as the Server Edition and the Enterprise Edition.

A data extraction and transformation program for Windows NT/2000 servers that is used to pull data from legacy databases, flat files and relational databases and convert them into data marts and data warehouses. Formerly a product from Ascential Software Corporation, which IBM acquired in 2005, DataStage became a core component of the IBM WebSphere Data Integration suite.

DataStage originated at VMark[1], a spin off from Prime Computers that developed two notable products: UniVerse database and the DataStage ETL tool.


The first VMark ETL prototype was built by Lee Scheffler in the first half of 1996[1].

Peter Weyman was VMark VP of Strategy and identified the ETL market as an opportunity. He appointed Lee Scheffler as the architect and conceived the product brand name "Stage" to signify modularity and component-orientation[2].

This tag was used to name DataStage and subsequently used in related products QualityStage, ProfileStage, MetaStage and AuditStage.

Lee Scheffler presented the DataStage product overview to the board of VMark in June 1996 and it was approved for development.

The product was in alpha testing in October, beta testing in November and was generally available in January 1997.

VMark acquired UniData in October 1997 and renamed itself to Ardent Software[3]. In 1999 Ardent Software was acquired by Informix[4] the database software vendor.

In April 2001 IBM acquired Informix and took just the database business leaving the data integration tools to be spun off as an independent software company called Ascential Software[5].

In November 2001, Ascential Software Corp. of Westboro, Mass. acquired privately held Torrent Systems Inc. of Cambridge, Mass. for $46 million in cash.

Ascential announced a commitment to integrate Orchestrate's parallel processing capabilities directly into the DataStageXE platform. [6].

In March 2005 IBM acquired Ascential Software[7] and made DataStage part of the WebSphere family as WebSphere DataStage.

In 2006 the product was released as part of the IBM Information Server under the Information Management family but was still known as WebSphere DataStage.

In 2008 the suite was renamed to InfoSphere Information Server and the product was renamed to InfoSphere DataStage[8].

•Enterprise Edition: a name give to the version of DataStage that had a parallel processing architecture and parallel ETL jobs.

•Server Edition: the name of the original version of DataStage representing Server Jobs. Early DataStage versions only contained Server Jobs. DataStage 5 added Sequence Jobs and DataStage 6 added Parallel Jobs via Enterprise Edition.

•MVS Edition: mainframe jobs, developed on a Windows or Unix/Linux platform and transferred to the mainframe as compiled mainframe jobs.

•DataStage for PeopleSoft: a server edition with prebuilt PeopleSoft EPM jobs under an OEM arragement with PeopleSoft and Oracle Corporation.

•DataStage TX: for processing complex transactions and messages, formerly known as Mercator.

•DataStage SOA: Real Time Integration pack can turn server or parallel jobs into SOA services.




Monday, June 30, 2008

Aggregator Stage

Grouping Keys Category

Group. Specifies the input columns you are using as group keys. Repeat the property to select multiple columns as group keys. You can use the Column Selection dialog box to select several group keys at once if required.

This property has a dependent property:

Case Sensitive. Use this to specify whether each group key is case sensitive or not, this is set to True by default, i.e., the values “CASE” and “case” in would end up in different groups.

Aggregations Category

Aggregation Type. This property allows you to specify the type of aggregation operation your stage is performing. Choose from Calculate (the default), Recalculate, and Count Rows.

Column for Calculation. The Calculate aggregate type allows you to summarize the contents of a particular column or columns in your input data set by applying one or more aggregate functions to it.

Select the column to be aggregated, then select dependent properties to specify the operation to perform on it, and the output colum to carry the result. You can use the Column Selection dialog be to select several columns at once if required.

Count Output Column. The Count Rows aggregate type performs a count of the number of records within each group. Specify the column on which the count is output.

Summary Column for Recalculation. This aggregate type allows you to apply aggregate functions to a column that has already been summarized. This is like calculate but performs the specified aggregate operation on a set of data that has already been summarized. In practice this means you should have performed a calculate (or recalculate ) operation in a previous Aggregator stage with the Summary property set to produce a subrecord containing the summary data that is then included with the data set. Select the column to be aggregated, then select dependent properties to specify the operation to perform on it, and the output column to carry the result. You can use the Column Selection dialog box to select several columns at once if required.

Default To Decimal Output. The output type of a calculation or recalculation column is double. Setting this property causes it to default to decimal. You can also set a default precision and scale. (You can also specify that individual columns have decimal output while others retain the default type of double.)

Weighting column. This is a dependent property of Count Output Column or Column for Calculation. Configures the stage to increment the count for the group by the contents of the weight column for each record in the group, instead of by 1. Not available for Summary Column for Recalculation. Setting this option affects only the following options:

Percent Coefficient of Variation.

Mean Value

Sum

Sum of Weights

Uncorrected Sum of Squares

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