Donation tracking w/two types of donors

[Mandu]

I've got a design question here. I'm tracking donations, which can come from either Individuals or Groups. A donation consists simply of a date and a dollar amount (and maybe check number). I think that Individuals and Groups belong in separate tables, but that Donations are donations, whether from an individual or a group, and thus should be in a single table.

A Donation should link back to the entity that gave it, either Indiv or Group.

The relationship from both Individual and Group to Donation is one-to-many (although any single Donation has exactly one donor).

I want the user interface for entering donations to be as simple as possible, hiding from the end user the distinction between individual and group wherever possible and "reasonable". I don't know if it's easier, for example, for the data entry person to work with a single list of merged Group and Individual names, or to keep those as separate lists. That sort of thing.

I'd appreciate some guidance with this problem!

Thanks,

Chap

[David Jondreau]

Individuals and Groups probably belong in the same table, "Donors" with a field for "Type" (which can be Individual or Group).

[Mandu]

Individuals and Groups probably belong in the same table, "Donors" with a field for "Type" (which can be Individual or Group).

Thanks, David.

To make sure I understand you, are you suggesting an additional table (Donors) that is parent to multiple Donations, and that refers back to either an Individuals record or a Groups record, depending upon the Type?

[David Jondreau]

I hadn't intended it that way. I meant combine the two tables, Individuals and Groups, into one table, Donors. But if the two tables are sufficiently different I think your interpretation might work. It depends on why you think they should be separate, but think the former will be easier.

[Søren Dyhr]

But as such are individuals usually participants in a group as well:

http://jonathanstark.com/recursive_data_structures.php

...it's just if the groups here fit each individual? Otherwise make an attribute to distinguise them - but this have already been suggested.

--sd

[Mandu]

Soren,

Thanks for the link! Very useful.

In my case, the individuals and groups are not related in the way you speculated (i.e. neither parent/child, nor recursively). They have almost no fields in common beyond a mailing address. I can't see combining Indivs and Groups into a single table, but I think I will define a table "Donors" that has a one-to-one relationship with Indivs and Groups and contains a certain amount of (redundant) info, like mailing address, from its related Indiv or Group record. A Donors record will be parent to multiple Donations records.