problem with lookup command

[abhayneilam]

Hi,

I have a master .csv file in which I have 10 rows, now I have one more child file which contains only 4 rows, now I want to lookup with the 4 rows in the 10 rows , if found, replace one of the column in master file

in my child.csv , only two columns "A" and "B"
in my master.csv, many columns, "A","B","C","D"

I have to match child.csv column "A" with master.csv column "A" and replace the value of column "B" of master.csv with the value of column "B" of child.csv

|inputlookup "masterfile.csv"|....| lookup "child.csv" field_name

but in this case what is happening is , value is getting replaced for the matched data but other values are becoming null

I dont want that value to become null, unmatched value will remain same, only matched value will replace

[OL]

Hello,

Can you tried to use the "join type=left" yet?

The idea I have is something like:

|inputlookup "masterfile.csv"| join type=left A [| inputlookup "child.csv" | rename B as B_new]| eval B = if(isnotnull(B_new), B_new, B)| outputlookup "masterfile.csv"

Hope it helps.
Regards,
Olivier