adding if to lookup is the value of lookup is fetched to 0

[rdsuperlike]

I am trying to add days from two different lookups to the out_date to generate fg_out_date.

I am getting the results from below part of the script. But still some scenarios are not giving any data

eg:

Out date          processing_days          LEAD TIME_D           FG Out Date

01/15/2015                2                             2                               1/19/2015 (gives desired result)

01/15/2015                 0                             2                                doesnt give anything, should give 1/17/2015

01/15/2015                 2                            0                               doesnt give anything, should give 1/17/2015

01/15/2015                 2                            0                               doesnt give anything, should give 1/17/2015

01/15/2015                  0                            0                                  doesnt give anything, should give 1/15/2015

If(STAGE = 'abc',floor(Date(OUT_DATE + Lookup ('processing_days','PPS_key',FW_QCDA_VENDOR_NAME &'-' & ITEM_NAME,'Part_Attributes') - 7

+ Lookup('LEAD TIME_D','DIE_LEADTIME_ITEM_TYPE_REC_TYPE_CODE',PO_ITEM_ITEM_TYPE &'-' & FW_TYPE,'DIE_LEADTIME')))

,floor(Date(OUT_DATE + Lookup ('processing_days','PPS_key',FW_QCDA_VENDOR_NAME &'-' & ITEM_NAME,'Part_Attributes')

+ Lookup('LEAD TIME_D','DIE_LEADTIME_ITEM_TYPE_REC_TYPE_CODE',PO_ITEM_ITEM_TYPE &'-' & FW_TYPE,'DIE_LEADTIME'))))

  as FG_OUT_DATE

Any input is appreciated here

[Gysbert_Wassenaar]

Can you post a document that demonstrates the problem?