Delete the foreign key referenced by a table field, save it, and re-Add the previously deleted foreign key after data import.

Create   Procedure Genforeignkey
@ Tablename   Varchar ( 200 ) -- Name of the table in the foreign key database to be added
As
Declare   @ Cur   Cursor
Declare   @ FK   Varchar ( 100 )
Declare   @ Execsql   Varchar ( 8000 )

Begin

Declare   @ SQL   Varchar ( 8000 )
Set   @ SQL = ''
Select @ SQL   =   @ SQL
+ Char ( 13 ) + ' ALTER TABLE ' + A. vt
+   ' Add constraint FK _ ' + Vt + ' _ ' + VF + ' _ ' + Vr + ' _ ' + VP +
' Foreign key ( ' + VF + ' )
References ' + Vr + ' ( ' + VP + ' ) '
From  
(

Select Primary Key column ID = B. rkey
, VP = ( Select Name From Syscolumns Where Colid = B. rkey And ID = B. rkeyid)
, Vt = Object_name (B. fkeyid)
, Vr =Object_name(B. rkeyid)
, Foreign key column ID = B. fkey
, VF = ( Select Name From Syscolumns Where Colid = B. fkey And ID = B. fkeyid)
From Sysobjects
Join Sysforeignkeys B On A. ID = B. constid
Join Sysobjects C On A. parent_obj = C. ID
Where A. xtype = ' F '   And C. xtype = ' U '
And   Object_name (B. fkeyid) =   @ Tablename
)
Print   @ SQL
Set   @ Cur   =   Cursor Read_only
For
Select So. Name
From Sysforeignkeys SF
Join Sysobjects so On SF. constid = So. ID
Join Sysobjects so1 On SF. fkeyid = So1.id
Where So1.name = @ Tablename

Open   @ Cur
Fetch   Next   From   @ Cur   Into   @ FK

While ( @ Fetch_status   =   0 )
Begin
Set   @ Execsql   =   ' ALTER TABLE ' + @ Tablename + ' Drop Constraint '   +   @ FK
Exec ( @ Execsql )

Fetch   Next   From   @ Cur   Into   @ FK
End

Close   @ Cur
Deallocate @ cur
End
Go