Left join calculation

[jjustingkm]

I have a two tables joined like below

A:

SELECT X,Y FROM TABLE1;

B:

LEFT JOIN(A)

SELECT Z FROM TABLE2.

I have to do a calculation using both X and Z, I think I should be able to do it using a resident table , but just wants to know, Is it possible to in the existing script itself.

Thanks in advance,

[Lisa_P]

When you join the tables there must be something in common to join on.

[Vegar]

No, you will not be able to combine Z with X nor Y until the Join is complete. 

However, if you have one Z value per A-record then you could consider  using an mapping  table an applymap() to get the value at the same time as you load X and Y from A.

Map:

MAPPING LOAD [ID], [Z] FROM SourceB

A:

LOAD *, Applymap('Map', [ID]) as Z FROM SourceA;

[jjustingkm]

Got, but in this case its a calculation after the join is complete, so I have to go for the resident table. Thanks for the reply.