SQL 2008/11/11

NeoYang

01.在classes資料表中找出有幾位學生選修CS213

1. Select Count(*) From Classes Where c_no = 'CS213'

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02.在classes表中統計每一間教室提供給幾門課程表作為教室

1. Select room,Count(*) From Classes Group By room

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03.找出教授兩門課程以上的老師名單

1. Select name from Instructors
   
2. Where Exists(
   
3. Select eid,Count(*) From Classes
   
4. Where Classes.eid = Instructors.eid Group By eid
   
5. Having Count(*) >= 2)

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