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Sql 空表上的DuplicateKeyException_Sql_Linq - Fatal编程技术网

Sql 空表上的DuplicateKeyException

Sql 空表上的DuplicateKeyException,sql,linq,Sql,Linq,将实体添加到空表时,我会得到System.Data.Linq.DuplicateKeyException grade g = new grade(); g.subject = dc.subjects.Single(x => x.subjectID == 5); g.student = aStudent; dc.grades.InsertOnSubmit(g); 我把整张桌子都掉了下来,很不走运地重新造了一张。 Grades是一个连接表,主键和studentID为外键 有什么想法吗?存储为

将实体添加到空表时,我会得到System.Data.Linq.DuplicateKeyException

grade g = new grade();
g.subject = dc.subjects.Single(x => x.subjectID == 5);
g.student = aStudent;
dc.grades.InsertOnSubmit(g);
我把整张桌子都掉了下来,很不走运地重新造了一张。 Grades是一个连接表,主键和studentID为外键


有什么想法吗?

存储为下一个主键的主键可能有问题。请尝试以下操作:

DBCC CHECKIDENT("Grades", RESEED, 1)
您还应该像这样检查外键:

DBCC CHECKIDENT ("Subjects", NORESEED)