<div>According to ?setkey, setkey() doesn&#39;t return any value.  However, this was changed as of 1.6.5.</div><a href="https://r-forge.r-project.org/scm/viewvc.php/pkg/man/setkey.Rd?view=markup&amp;root=datatable">https://r-forge.r-project.org/scm/viewvc.php/pkg/man/setkey.Rd?view=markup&amp;root=datatable</a><div>

<a href="https://r-forge.r-project.org/scm/viewvc.php/pkg/NEWS?view=markup&amp;root=datatable">https://r-forge.r-project.org/scm/viewvc.php/pkg/NEWS?view=markup&amp;root=datatable</a></div><div><br></div><div>Could be a bit confusing.</div>

<div><br></div><div>Best,</div><div>Muhammad</div><div><br></div>