DSXchange

I have merge stage with one master link and 2 two update links.

Clarification1:we have two records(key=1,2) in master link and one record update1(key=1) link and two records in update2(key=1,2) link .

warn on unmatched masters=True

As per my understanding we do not have any value with key=2 in update1 so datastage
should generate warning but it is not generating.

Clarification2:
Unmatched master rows=Drop
As per my understanding we should get one row in output since key=2
is not found in update1 link but i am getting two rows.

Your understanding is not correct. In this context "unmatched" means across all Update links.

You use reject links for each Update link to capture stream rows for which no match was found.

Thanks for reply.I can understand now that it is not necessary to match all the update links.
even if it matches one record from update link it will show in o/p incase of unmatchedmastermode=drop

You use reject links for each Update link to capture stream rows for which no match was found

clarification1- stream rows means master link or update link.I think reject link will contain rows from update link

clarification2-Do we have any property to set reject links.I can add the reject links and it is capturing records from update link but it is working in all the below cases

Unmatched Master Mode-Drop/keep
warn on reject Updates-True/False

Clarification 1 - it's obvious that there is no row from the Update link in this case.

Clarification 2 - you can choose not to add reject links at all to the Merge stage.

@Clarification 2

where is that property to choose not to add reject links at all to the Merge stage

It's not a property. You simply don't draw the reject links in Designer.