can duplicates values allowed in join and concatenate?

[sbkumar]

what is main difference between join and concatenate?can  DUplicate values present if we use join and concatenate?

[tresesco · Accepted solution]

In both the cases duplicate values could be there. Have a look here:

Merging Data from Multiple Sources

Understanding Join and Concatenate | Qlikview Cookbook

Join Vs Concatenate