[datatable-help] What does "problem re-suffixing the merged data.table" mean?

[Allan Engelhardt]

Seems to work in 1.6.3, thanks.

Allan.

On 05/08/11 18:10, Steve Lianoglou wrote:
> Hi Allan,
>
> On Fri, Aug 5, 2011 at 10:56 AM, Allan Engelhardt (CYBAEA)
> <allane at cybaea.com>  wrote:
>> What does the warning mean?  What sort of problem?
>>
>> model.data<- merge(Y1, Y2, all = FALSE, suffixes = c(".Y1", ".Y2"))
>> Warning message:
>> In merge.data.table(Y1, Y2, all = FALSE, suffixes = c(".Y1", ".Y2")) :
>>   There was a problem re-suffixing the merged data.table. The merge was
>> succesful, but the default column naming has been used (ie. suffixes were
>> set to c('', '.1').
>>
>> It doesn't seem to matter what value I use for suffixes=
> When I added the ability to add custom suffixes, I added that warning
> if the logic I used to slap the right suffixes on the right columns
> hit a corner case that I didn't expect. The warning was so you could
> do what you did an report a problem so the logic could be revisited.
>
> Also, the merge actually "worked", though, the data.table that comes
> back is the one you would have gotten if you set the suffixes param to
> c("", ".1") [which was essentially what was happening before custom
> suffixes were supported).
>
> All that having been said, I recently checked in a fix for one of
> these corner cases that made it's way into data.table 1.6.3. Could you
> update to 1.6.3 to see if it works for you?
>
> If it doesn't, can you provide the column names of the two data.tables
> you are trying to merge on, and what the value is for your `by` param?
>
> Thanks,
> -steve
>