Teradata Enterprise

TD EE (Source/Lookup) invokes FastExport which produces 1 answer set. All the parallel processing is performed on the TD Server, not in DataStage. FastExport cannot handle selects that use unique key constraint that would only return one row. You have to be careful when using unique key constraints. This is set from the TD side and not by Datastage. If you use this 2 or 3 times for source tables/lookups in a job and you run a couple of jobs at once, then you have invoked too many fastexports. For explicit exports or big data pulls, the TD EE can work fine, or you can use the MLOAD stage (which does Fastexport if it is used as source stage)

 

TD EE (Target) invokes FastLoad for bulk loading into TD Tables. Fastload does not support Secondary Indexes in Teradata. TD EE Stage will create a work table when an append to a Teradata table is selected for the job. This is because a FastLoad must load to an empty table which is impossible with an append operation. To get around this, DataStage FastLoads to a generated empty work table and then does insert into (select * from work table) on the database side. Append option will create an empty TD table with ALL fields but NO defaults. It generates this empty table from the Teradata metadata, NOT your DataStage job metadata. Also, unknown columns are replaced with null.

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