如何创建外键 [英] how to create foreign key
问题描述
如何创建外键
i创建了两个表组织和管理器都具有ID coloumn如何在SQL studio 2005中继续
< blockquote>这样的事情:
ALTER TABLE 经理
ADD FOREIGN KEY (Id)
REFERENCES 组织(Id)
在这里查找更多详细信息:
http://www.w3schools.com/sql/sql_foreignkey.asp [ ^ ]
http://msdn.microsoft.com/en-us/library/ms175464(v = SQL.105)。如px [ ^ ]
参考: http:// msdn .microsoft.com / zh-CN / library / ms189049.aspx [ ^ ]
例如:CREATE TABLE 订单
(
O_Id int NOT NULL PRIMARY KEY ,
OrderNo int NOT NULL ,
P_Id int FOREIGN KEY 参考人员(P_Id)
)
要点:
列是人物表中的 PRIMARY KEY 。 />
Persons
表中的P_Id
订单
表中的P_Id
列是 FOREIGN KEY 在订单表中。
http://stackoverflow.com/questions/6340343/how-can-we-make-foreign-key-among-tables-after-inserting-那些数据表 [ ^ ]
< pre lang =sql> ALTER TABLE ORDERS
ADD FOREIGN KEY (customer_sid) REFERENCES CUSTOMER(SID);
how to create foreign key
i have created two tables organisation and manager both are having ID coloumn how to proceed in SQL studio 2005
Something like this:
ALTER TABLE Managers ADD FOREIGN KEY (Id) REFERENCES Organization(Id)
Look for more details here:
http://www.w3schools.com/sql/sql_foreignkey.asp[^]
http://msdn.microsoft.com/en-us/library/ms175464(v=sql.105).aspx[^]
Refer: http://msdn.microsoft.com/en-us/library/ms189049.aspx[^]
e.g:CREATE TABLE Orders ( O_Id int NOT NULL PRIMARY KEY, OrderNo int NOT NULL, P_Id int FOREIGN KEY REFERENCES Persons(P_Id) )
Key Point:
The"P_Id"
column in the"Persons"
table is the PRIMARY KEY in the "Persons" table.
The"P_Id"
column in the"Orders"
table is a FOREIGN KEY in the "Orders" table.
http://stackoverflow.com/questions/6340343/how-can-we-make-foreign-key-among-tables-after-inserting-data-in-those-tables[^]
ALTER TABLE ORDERS ADD FOREIGN KEY (customer_sid) REFERENCES CUSTOMER(SID);
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