11 lines
474 B
MySQL
11 lines
474 B
MySQL
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/*18. Write a query that extract the rows of all salesmen who have customers with more than one orders.*/
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SELECT *
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FROM salesman a
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WHERE EXISTS
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(SELECT * FROM customer b
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WHERE a.salesman_id=b.salesman_id
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AND 1<
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(SELECT COUNT (*)
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FROM orders
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WHERE orders.customer_id =
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b.customer_id));
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