Designer Guide

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Understanding the Transformations

The following table describes the function of each transformation in the slowly growing target mapping:

Transformation Name	Transformation Type	Description
SQ_ SourceName	Source Qualifier or Application Source Qualifier	Selects all rows from the source you choose in the Mapping Wizard.
LKP_GetData	Lookup	Caches the existing target table. Compares a logical key column in the source against the corresponding key column in the target.
EXP_DetectChanges	Expression	Uses the following expression to flag source rows that have no matching key in the target (indicating they are new): IIF(ISNULL(PM_PRIMARYKEY),TRUE,FALSE) Populates the NewFlag field with the results. Passes all rows to FIL_InsertNewRecord.
FIL_InsertNewRecord	Filter	Uses the following filter condition to filter out any rows from EXP_DetectChanges that are not marked new (TRUE): NewFlag . Passes new rows to UPD_ForceInserts.
UPD_ForceInserts	Update Strategy	Uses DD_INSERT to insert rows to the target.
SEQ_GenerateKeys	Sequence Generator	Generates a value for each new row written to the target, incrementing values by 1. Passes values to the target to populate the PM_PRIMARYKEY column.
T_ TargetName	Target Definition	Instance of the target definition for new rows to be inserted into the target.