How to identify only "not duplicated" rows
<p>I have a situation like this.
Multiple data.table "rbinded".</p>

<pre><code>library(data.table)
x &lt;-  data.table(id=c(1,2,3,4),dsp=c(5,6,7,8),status=c(FALSE,TRUE,FALSE,TRUE))
y &lt;-  data.table(id=c(1,2,3,4),dsp=c(6,6,7,8),status=c(FALSE,FALSE,FALSE,TRUE))
z &lt;- data.table(id=c(1,2,3,4),dsp=c(5,6,9,8),status=c(FALSE,TRUE,FALSE,FALSE))
w &lt;- data.table(id=c(1,2,3,4),dsp=c(5,6,7,NA),status=c(FALSE,TRUE,FALSE,TRUE))
setkey(x,id)
setkey(y,id)
setkey(z,id)
setkey(w,id)
Bigdt&lt;-rbind(x,y,z,w)
</code></pre>

<p>I would like to obtain ONLY the not repeated rows like:</p>

<pre><code>id  dsp status
1   6   FALSE
2   6   FALSE
3   9   FALSE
4   8   FALSE
4   NA  TRUE
</code></pre>

<p>So i tried </p>

<pre><code>Resultdt&lt;-Bigdt[!duplicated(Bigdt)]
</code></pre>

<p>but the result:</p>

<pre><code>id  dsp status
1   5   FALSE
2   6   TRUE
3   7   FALSE
4   8   TRUE
</code></pre>

<p>does not match my espectations.
I tried in different methods (as rbind is not mandatory), for example merge, join etc. the data.table package seems potentially the one that contains the solution...apparently. Any ideas?</p>