tMap: cannot refer to lookup data in inner join reject table because data turns empty

[mmctony]

Hi,

I'm running Talend Open Studio for Big Data-8.0.1.20211109_1610 (Community) and I'm experiencing a strange behaviour of tMap: when trying to inner join main flow with a lookup flow, I cannot output lookup record fields into reject table because all have default values (i.e. null, false, 0, ...).

I've attached a POC.

Is this behaviour expected? Any workaround?

 Thanks for your help,

Mick

[Anonymous · Accepted solution]

Hi

This is normal result, when doing an inner join, it takes the keys from main table and compare them with the keys from lookup table, output the unmatched data from main table to reject table. To get the unmatched keys from lookup table, change the lookup table as main table in another subjob.

Regards

Shong

[mmctony]

Hi Shong,

I got it. I've been confused by the fact that I'm joining rows that have the same key actually, in order to detect differences on other fields. That's why I've expected the lookup row not being null.

Thanks,

Mick