dhis2-devs team mailing list archive

[Bob Jolliffe <bobjolliffe@xxxxxxxxx>]

2009/3/19 Lars Helge Øverland <larshelge@xxxxxxxxx>:
>
>> So for India or for South Africa or Sri Lanka data
>> elements are "effectively" only members of one dataset?
>
>
> Not quite, a data element can be a member of many data sets, but those data
> sets cannot be entered by the same orgunit. I.e. data sets containing common
> data elements should be assigned to different orgunits in the hierarchy.
>

It seems to me that adding a PeriodType to the DataElement is
definitely redundant.

DataElement should always be a member of at least one DataSet - and
there is already be an (implicit) constraint that DataElements of a
DataSet will be of the same PeriodType.

What is probably required (if it doesn't yet exist) is an application
enforced constraint that a DataElement can only be a member of
different DataSets which share the same PeriodType.  Given that some
of those do exist (the bad practice) then it is considerably better to
rename (and re-id) the dataElement.  This will anyway be necessary if
DataElements become directly associated with PeriodType.

I think the only other thing which is achieved by associating the
PeriodType with the DataElement is that it would allow for DataSets
which a heterogenous mix of DataElement PeriodTypes, which I don't
think is a design goal.

Regards
Bob