Saturday, November 8, 2014

Informatica Powercenter Express - Joiner Transformation


Joiner transformation joins source data from two related heterogeneous sources from different locations or from different file systems. You can also join data from the same source. The Joiner transformation uses a condition that matches one or more pairs of columns between the two sources.

Joiner Ports
The two input pipelines include a master pipeline and a detail pipeline or a master and a detail branch. The master pipeline ends at the Joiner transformation, while the detail pipeline continues to the target.
Master
Ports that link to the master source in the mapping.
Detail
Ports that link to the detail source in the mapping.

Join Types
The Joiner transformation supports the following types of join
Normal Join
In this join, the Data Integration Service discards all rows of data from the master and detail source that do not match, based on the condition.
Master Outer Join
This join keeps all rows of data from the detail source and the matching rows from the master source. It discards the unmatched rows from the master source.
Detail Outer Join
This join keeps all rows of data from the master source and the matching rows from the detail source. It discards the unmatched rows from the detail source.
Full Outer Join
This join keeps all rows of data from both the master and detail sources.

Advanced properties for joiner transformation

Joiner Data Cache Size
Data cache size for the transformation. Default is Auto.
Joiner Index Cache Size
Index cache size for the transformation. Default is Auto.
Cache Directory
Local directory where the Data Integration Service creates the index cache files and data cache files. Default is the CacheDir system parameter.
Sorted Input
Indicates that input data is presorted by groups. Choose Sorted Input to join sorted data.
Master Sort Order
Specifies the sort order of the master source data. Choose Ascending if the master source data is in ascending order.
Tracing Level
Amount of detail that appears in the log for this transformation. Default is normal.

Tips to Improve performance while using Joiner Transformation

  • Designate the master source as the source with fewer duplicate key values.  If the master source contains many rows with the same key value, the Data Integration Service must cache more rows, which can decrease performance.
  • Designate the master source as the source with fewer rows. The Joiner transformation compares each row of the detail source against the master source. The fewer rows in the master, the fewer iterations of the join comparison occur, which speeds the join process.
  • Perform joins in a database when possible. Performing a join in a database is faster than performing a join in during the mapping run . The type of database join you use can affect performance. Normal joins are faster than outer joins and result in fewer rows. 
  • Join sorted data when possible. The Data Integration Service increases performance by minimizing disk input and disk output. You see the greatest performance increase when you work with large data sets.

Scenario for Joiner transformation

Join the department name from department table to employee table


*In case of any questions, feel free to leave comments on this page and I would get back as soon as I can.

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