Outer Join
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Outer Join
Want to implement SCD Type II in Server Version, and due to that i want to do Outer join what is the process.
nsd
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Write out your processing specification (what is to happen in all cases) in English. You will find that this guides your thoughts.
For example, the generic Type 2 SCD needs to make two choices. Therefore there are two IF tests in the following pseudo code.
I don't see a need for an "outer join" anywhere in that algorithm, except that a reference lookup is inherently an outer join.
For example, the generic Type 2 SCD needs to make two choices. Therefore there are two IF tests in the following pseudo code.
Code: Select all
If (row exists in target table)
Then
If (change detected in appropriate columns(s)
Then
generate new SK value
insert new row
mark existing row in target as no longer current
End
End
Else
generate new SK value
insert new row
End
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Any contribution to this forum is my own opinion and does not necessarily reflect any position that IBM may hold.
Any contribution to this forum is my own opinion and does not necessarily reflect any position that IBM may hold.