Re: Building a tree recursively

This is a multi-part message in MIME format. --------------CB15BB1AD6D7FF0F18F5BD13 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Scott: You could use a prepared cursor, I mean LET sqlstmt= "select child_no from unit_link where parent_no = ?" PREPARE ex_sql FROM sqlstmt DECLARE child CURSOR FOR ex_sql then you just use OPEN USING, without need to close-reopen the cursor. Anyway, this won't produce what you want, since the cursor are not recursive. So, I have done this using an array in INFORMIX-4GL for store the children records. Scott Black wrote: > I know someone out there must have done this before... > > I have a table: > unit_link( > parent_no integer, > child_no integer... > > Each child can have children of it's own, for as many levels as > necessary. I tried to build a recursive function call to build the tree > as follows: > > function get_children(unit_no) > > declare child cursor for > select child_no > from unit_link > where parent_no = unit_no> > foreach child into this_unit > call get_children(this_unit)... > > By now you see the problem. On the second time through I get error -400 > (Fetch attempted on unopen cursor). Tech support says that this is the > way it is designed, you cannot re-use a cursor without first closing it. > It seems to me that each recursive call should be within it's own stack > and that re-using variables, cursors and the like should not be a > problem, but... > > Is there another way to go about this w/o recursion? What methods have > any of you used to solve similar problems? > > TIA > BTW this is HP-UX 10.20 OnLine 7.22 4GL 6.04 --------------CB15BB1AD6D7FF0F18F5BD13 Content-Type: text/x-vcard; charset=us-ascii; name="vcard.vcf" Content-Transfer-Encoding: 7bit Content-Description: Card for Melvin Perez Content-Disposition: attachment; filename="vcard.vcf" begin: vcard fn: Melvin Perez n: Perez;Melvin org: CAM Informatica. S. A. email;internet: cam@codetel.net.do title: Technical Vicepresident tel;work: (809) 686-5574 tel;fax: (809) 686-5467 tel;home: (809) 227-2893 x-mozilla-cpt: ;-960 x-mozilla-html: FALSE version: 2.1 end: vcard --------------CB15BB1AD6D7FF0F18F5BD13--