Delete all the foreign key relation in your SQL Server database

DECLARE @cmd nvarchar(1000)

DECLARE @fk_table_name nvarchar(1000)

DECLARE @fk_name nvarchar(1000)

DECLARE cursor_fkeys CURSOR FOR

   SELECT  OBJECT_NAME(fk.parent_object_id) AS fk_table_name,

                  fk.name as fk_name

   FROM    sys.foreign_keys fk  JOIN 

           sys.tables tbl ON tbl.OBJECT_ID = fk.referenced_object_id

   -- WHERE OBJECT_NAME(fk.parent_object_id) in ('table1', 'table2', 'table2')

OPEN cursor_fkeys

FETCH NEXT FROM cursor_fkeys

      INTO @fk_table_name, @fk_name

WHILE @@FETCH_STATUS=0

BEGIN

      -- build alter table statement

      SET @cmd = 'ALTER TABLE [' + @fk_table_name + '] DROP CONSTRAINT [' + @fk_name + ']'

      -- execute it

      exec dbo.sp_executesql @cmd

      FETCH NEXT FROM cursor_fkeys

      INTO @fk_table_name, @fk_name

END

CLOSE cursor_fkeys

DEALLOCATE cursor_fkeys