判断两个地址是否有60%的内容相符的函数要怎么写?

Question

create function f_str(@address1 varchar(100),@address2 varchar(100))
returns int
as
begin
       declare @i int
       set @i=0
 
       --省份相同
       if left(@address1,charindex('省',@address1))=left(@address2,charindex('省',@address2))
          set @i=i+1
       
       select @address1=stuff(@address1,1,charindex('省',@address1),''),
              @address2=stuff(@address2,1,charindex('省',@address2),'')       --市相同
       if left(@address1,charindex('市',@address1))=left(@address2,charindex('市',@address2))
          set @i=i+1
 
       --其它依此类推       return @i
end
go