On a blog I read a proposal to replace many tables like this:
lookup_genders
0 | Unknown
1 | Female
2 | Male
lookup_countries
0 | Unknown
1 | Germany
2 | UK
3 | USA
into a single table like this:
lookups
0 | Unknown | Gender
1 | Female | Gender
2 | Male | Gender
4 | Germany | Country
5 | UK | Country
6 | USA | Country
The reason provided there was to get rid of many almost identical O/R mappings.
Is this a really good idea? Which problems could arise? Under which conditions would this be a good idea?
Best Answer
The first time you want to add a new property to your countries, you are in trouble. For example, what would be the capital of 'Female' ?