Some beers are not the best seller of any manufacturer so a rounded arrow to

Some beers are not the best seller of any

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Some beers are not the best-seller of any manufacturer, so a rounded arrow to Manfs would be inappropriate. But a beer manufacturer has to have a best-seller. Manfs Beers Best- seller
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108 Attributes on Relationships Sometimes it is useful to attach an attribute to a relationship.
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109 Attributes on Relationships Sometimes it is useful to attach an attribute to a relationship. Think of this attribute as a property of tuples in the relationship set.
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110 Attributes on Relationships Sometimes it is useful to attach an attribute to a relationship. Think of this attribute as a property of tuples in the relationship set. Example. Price is a function of both the bar and the beer, not of one alone. Bars Beers Sells price
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111 Attributes on Relationships Sometimes it is useful to attach an attribute to a relationship. Think of this attribute as a property of tuples in the relationship set. Example. Price is a function of both the bar and the beer, not of one alone. Equivalently, you can create an entity set representing values of the attribute, and make that entity set participate in the relationship. Bars Beers Sells price
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112 Attributes on Relationships Sometimes it is useful to attach an attribute to a relationship. Think of this attribute as a property of tuples in the relationship set. Example. Price is a function of both the bar and the beer, not of one alone. Equivalently, you can create an entity set representing values of the attribute, and make that entity set participate in the relationship. Bars Beers Sells price Bars Beers Sells price Prices
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113 Attributes on Relationships Sometimes it is useful to attach an attribute to a relationship. Think of this attribute as a property of tuples in the relationship set. Example. Price is a function of both the bar and the beer, not of one alone. Equivalently, you can create an entity set representing values of the attribute, and make that entity set participate in the relationship. Bars Beers Sells price Bars Beers Sells price Prices Note convention: arrow from multiway relationship means “all other entity sets together determine a unique one of these.”
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