Denormalization

• Add rname field to player to avoid join:

  • newplayer (id, name, num, pos, tname, tcity, rname FK references rink(rname), FK (tname, tcity) references team (tname, city))
  • newplayer is 2NF (YIKES!)
  • DB is still lossless, dependency-preserving

• Must manage redundancy!

  • Updates to newplayer (tname, tcity, rname) must check for correct value of rname
  • Updates to team (rname) must propagate to newplayer

• Create a view to preserve external schema

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