Question

I have a table ‘tReferences’ with this fields:

IDFILE [int],
NAME [varchar(255)],
IDREFERENCE [int]

1             FILE1     0
2             FILE2     0
3             FILE3     0
4             FILE4     1
5             FILE5     4
6             FILE6     4
7             FILE7     2
8             FILE8     3

I have to create a recursive stored procedure that can show all references for a specifically IDFILE.

Results:

IDFILE   NAME   LEVEL
1             FILE1     0
4             FILE4     1
5             FILE5     2
6             FILE6     2

How can I do that?

Thank you very much.

Answer 1

To this I create a new temporary table:

#tempT (
 IDFILE [int],
 NAME [varchar(255)],
 IDREFERENCE [int]
 level int
)

and I populate this table in this way:

declare @parent int;
declare @level int;
set @parent = 1
set @level = 0

insert into  #tempT 
select * from tReferences where IDFILE = @parent

while @@rowcount > 0
begin
   insert into  #tempT 
     select *, @level from tReferences 
     where 
       IDREFERENCE in (select IDFILE from #tempT )
           and
       IDFILE not in (select IDFILE from #tempT )
   set @level = @level + 1

end

then, I return

select idfile, name, level from #tempT