我正在制作一個學校管理程序，在該程序中我想將多個表連接到學生表，我想將城市 ID 字段用于學生出生地和表中的實際地址，但我無法弄清楚怎么做。SELECT Students.StudentID, Students.Name, Students.Birthday, Students.MothersName, Classes.ClassName, Cities.Name, Cities.Name,PostalCode.PostalCode, Street.StreetName, Students.NumberFROM StudentsINNER JOIN Classes ON Students.ClassID = Classes.ClassIDINNER JOIN Cities ON Students.BirthPlaceID = Cities.CityIDINNER JOIN Cities ON Students.CityID = Cities.CityIDINNER JOIN PostalCode ON Students.PostalCodeID = PostalCode.PostalCodeIDINNER JOIN Utca ON Students.StreetID = Streets.StreetID我已經嘗試過這種方式，但只會導致錯誤。
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翻閱古今
TA貢獻1780條經驗 獲得超5個贊
您在選擇中為表創建別名，然后您可以使用 2 個不同的標識訪問同一個表。我對您的 select 語句中的值執行了相同的操作（創建別名），以確定哪個城市是哪個城市。
SELECT Students.StudentID, Students.Name, Students.Birthday, Students.MothersName, Classes.ClassName, StudentBirthCities.Name as StudentBirthCityName, StudentCity.Name as StudentCityName,
PostalCode.PostalCode, Street.StreetName, Students.Number
FROM Students
INNER JOIN Classes ON Students.ClassID = Classes.ClassID
INNER JOIN Cities StudentBirthCities ON Students.BirthPlaceID = StudentBirthCities.CityID
INNER JOIN Cities StudentCity ON Students.CityID = StudentCity.CityID
INNER JOIN PostalCode ON Students.PostalCodeID = PostalCode.PostalCodeID
INNER JOIN Utca ON Students.StreetID = Streets.StreetID
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