First page Back Continue Last page Graphics
Beer example 3
S.b(S V L) Ç L.b(L)
The first part selects the beers that are served in a bar where a visitor comes who likes that beer.
The second part lists all the beers liked by anyone, so that's just the list of all the beers.
Since the second part are all the beers the intersection results in just the first part.
Conclusion: List all the beers that are served in a bar where a visitor comes who likes that beer.
Notes:
Deze query komt van Jonaro Wever (foute uitwerking voor bier vraag n).