full outer join

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mystuff
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full outer join

Post by mystuff »

I am slightly puzzled with the datastage full outer join. I have Key fields and values. the full outer join drops off common fiels (other than the key fields , or join fields).

Can anyone tell me on what basis it drops the records.

Shouldn't it be the other way i.e. dropping common key fields and retaining other fields from both inputs.
ArndW
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Post by ArndW »

The full outer join will combine table contents, never drop rows. See http://en.wikipedia.org/wiki/Join_(SQL)#Full_outer_join for a good description of the join functionality.
ray.wurlod
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Post by ray.wurlod »

It drops common key fields because they are identically valued and identically named. You can avoid this by using different naming conventions on the two inputs. A Copy stage is the most efficient stage for simply renaming columns.
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