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Exercise: RA Set Operations

Use RA to construct answer relations for these queries:

  1. Bars where either Gernot or John drink.
  2. Bars where both Gernot and John drink.
  3. Beers which both Andrew and John like.
  4. Bars which sell New and VB.
  5. Which bars are going broke? (i.e. have no drinkers)
  6. Which beers are not available at any bar?