Attribute oval with a line to the rectangle representing its entity set Example

Attribute oval with a line to the rectangle

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Attribute = oval, with a line to the rectangle representing its entity set. Example Entity set Beers has two attributes, name and manf (manufacturer)
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72 E/R Diagrams In an entity-relationship diagram: Entity set = rectangle. Attribute = oval, with a line to the rectangle representing its entity set. Example Entity set Beers has two attributes, name and manf (manufacturer) Each Beers entity has values for these two attributes. e.g. (Bud, Anheuser-Busch)
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73 E/R Diagrams In an entity-relationship diagram: Entity set = rectangle. Attribute = oval, with a line to the rectangle representing its entity set. Example Entity set Beers has two attributes, name and manf (manufacturer) Each Beers entity has values for these two attributes. e.g. (Bud, Anheuser-Busch) Beers name manf
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74 Relationships A relationship connects some entity sets.
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75 Relationships A relationship connects some entity sets. It is given by a diamond, with lines to each of the entity sets involved.
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76 Relationships A relationship connects some entity sets. It is given by a diamond, with lines to each of the entity sets involved. Drinkers addr name Beers manf name Bars name license addr
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77 Relationships A relationship connects some entity sets. It is given by a diamond, with lines to each of the entity sets involved. Drinkers addr name Beers manf name Bars name license addr Bars sell some beers.
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78 Relationships A relationship connects some entity sets. It is given by a diamond, with lines to each of the entity sets involved. Drinkers addr name Beers manf name Bars name license addr Sells Bars sell some beers.
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79 Relationships A relationship connects some entity sets. It is given by a diamond, with lines to each of the entity sets involved. Drinkers addr name Beers manf name Bars name license addr Sells Bars sell some beers. Likes Drinkers like some beers .
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80 Relationships A relationship connects some entity sets. It is given by a diamond, with lines to each of the entity sets involved. Drinkers addr name Beers manf name Bars name license addr Sells Bars sell some beers. Likes Drinkers like some beers . Frequents Drinkers frequent some bars .
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81 Relationship Set The current “ value ” of an entity set is the set of entities that belong to it. Example: the set of all bars in our database. The “ value ” of a relationship is a set of lists of currently related entities, one from each of the related entity sets. Bar Beer Joe’s Bar Bud Joe’s Bar Miller Sue’s Bar Bud Sue’s Bar Pete’s Ale Sue’s Bar Bud Lite For the relationship Sells , we might have a relationship set like:
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82 Multiway Relationships Sometimes, we need a relationship that connects more than two entity sets.
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83 Multiway Relationships Sometimes, we need a relationship that connects more than two entity sets.
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