Correct Ternary Mapping?

Asked Jan 23 '20 at 13:29

Active Jan 23 '20 at 13:29

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I want to create an Entity-Relationship-Modell for my Database. But i have Problems with thr ternary Relationship. How should this look like for the sql code below?

ternary Relationship1

CREATE TABLE sell(
employee_id INTEGER,
serial_number CHAR(9),
customer_id INTEGER,
PRIMARY KEY (serial number),
FOREIGN KEY(employee_id) REFERENCES Employee(employee_id) ON DELETE CASCADE,
FOREIGN KEY(serial_number) REFERENCES Product(serial_number) ON DELETE CASCADE,
FOREIGN KEY(customer_id) REFERENCES Customer(customer_id) ON DELETE CASCADE
);

asked Jan 23 '20 at 13:29

myworld

https://stackoverflow.com/questions/18365870/er-diagram-ternary-relationship-how-to-read-properly – Honeyboy Wilson Jan 23 '20 at 13:49
serial_number? char(9)? – jarlh Jan 23 '20 at 13:52
@HoneyboyWilson from what i have understand my Relationship has to look like this 1:1:n? (n for Products) – myworld Jan 23 '20 at 13:56
@jarlh should i take Integer? – myworld Jan 23 '20 at 13:57

Correct Ternary Mapping?

0 Answers0