On Mon, Mar 10, 2008 at 02:01:16AM +0000, Ying Zhang wrote:

Update of /cvsroot/monetdb/pathfinder/runtime In directory sc8-pr-cvs16.sourceforge.net:/tmp/cvs-serv3350

Modified Files: Tag: xquery-decomposition xrpc_client.mx Log Message:

• adopt Stefan's tips: used rangesplit to split item|kind per container

(Thanks!).

• a lot of corrections to get this thing working

Index: xrpc_client.mx

RCS file: /cvsroot/monetdb/pathfinder/runtime/xrpc_client.mx,v retrieving revision 1.41.2.8 retrieving revision 1.41.2.9 diff -u -d -r1.41.2.8 -r1.41.2.9 --- xrpc_client.mx 8 Mar 2008 21:17:27 -0000 1.41.2.8 +++ xrpc_client.mx 10 Mar 2008 02:01:13 -0000 1.41.2.9 @@ -94,94 +94,40 @@ BAT[void, dbl] dbl_values, BAT[void, dbl] dec_values, BAT[void, str] str_values) : oid {

• var maxnconts := ws.fetch(0).count(); # split used_<item|kind> into multiple BATs according to their container IDs

vvvvvvvvv

 var uitems := bat(oid, bat, maxnconts); # container ID in head
 var ukinds := bat(oid, bat, maxnconts);

^^^^^^^^^ These two BATs are IMHO overwritten below (see "vvvvvvvvv"/"^^^^^^^^^"); hence, no (more) need to make them, here!??

• var conts := used_kind.[int]().[>>](6).tsort(); # [oid,int]: container IDs in tail
• var nconts := conts.tunique().count();
• if(nconts = 1){ # all items are from the same container

•    uitems.insert(conts.fetch(0).oid(), used_item);
  

•    ukinds.insert(conts.fetch(0).oid(), used_kind);
  

• } else {

•    # sort used_<item|kind> on container ID
  

•    var itemcont := used_item.reverse().join(conts).reverse().tmark(0@0);
  

•    var kindcont := used_kind.reverse().join(conts).reverse().tmark(0@0);
  

•    var curcont := conts.fetch(0);
  

•    var tmpitem := bat(void, oid).seqbase(0@0);
  

•    var tmpkind := bat(void, int).seqbase(0@0);
  

•    conts := conts.tmark(0@0); # conts[void,int]
  

•    conts@batloop(){
  

•        # start of next container, save items|kinds of previous container
  

•        if($t != curcont) {
  

•            curcont := $t;
  

•            uitems.insert(curcont, tmpitem);
  

•            ukinds.insert(curcont, tmpkind);
  

•            tmpitem := bat(void, oid).seqbase(0@0);
  

•            tmpkind := bat(void, int).seqbase(0@0);
  

•        }
  

•        tmpitem.append(itemcont.fetch($h));
  

•        tmpkind.append(kindcont.fetch($h));
  

•    }
  

•    uitems.insert(curcont, tmpitem);
  

•    ukinds.insert(curcont, tmpkind);
  

• }

• var conts := get_container([int](used_kind)); # [oid,int]: container IDs in tail
• var unq_conts := tunique(conts).hmark(0@0);
• var nconts := count(unq_conts);
• var rs := rangesplit(conts, nconts).tmark(0@0).reverse().join(unq_conts).reverse();

This will do want you want (have rs's head contain the conts from the BATs in its tail) ONLY if tunique(conts) & rangesplit(conts, nconts) happen to produce the same order! To be sure, you'd need to sort the unq_conts before marking them (result of rangesplit shoiuld hopefully be sorted): var unq_conts := tunique(conts).sort().hmark(0@0); Was there something wrong with my proposal: var rs := rangesplit(conts, nconts); rs := rs.reverse().mirror().[fetch](0).reverse(); ?

vvvvvvvvv

• uitems := rs.[mirror]().[leftfetchjoin](const used_item);
• uitems := [tmark](uitems, const 0@0);
• ukinds := rs.[mirror]().[leftfetchjoin](const used_kind);
• ukinds := [tmark](ukinds, const 0@0);

^^^^^^^^^ (see "vvvvvvvvv"/^^^^^^^^^" above) Plus: It might be more efficient to get rid of the head before the join, since you "overwrite" them afterwards, anyway; i.e.: uitems := rs.[tmark](oid(nil)).[leftfetchjoin](const used_item).[tmark](uitems, const 0@0);

 # split returned_<item|kind> into multiple BATs according to their container IDs

vvvvvvvvv

 var ritems := bat(oid, bat, maxnconts); # container ID in head
 var rkinds := bat(oid, bat, maxnconts);

^^^^^^^^^ Same as with uitems/ukinds above.

• conts := returned_kind.[int]().[>>](6).tsort(); # [oid,int]: container IDs in tail
• nconts := conts.tunique().count();
• if(nconts = 1){ # all items are from the same container

•    ritems.insert(conts.fetch(0).oid(), returned_item);
  

•    rkinds.insert(conts.fetch(0).oid(), returned_kind);
  

• } else {

•    # sort used_<item|kind> on container ID
  

•    var itemcont := returned_item.reverse().join(conts).reverse().tmark(0@0);
  

•    var kindcont := returned_kind.reverse().join(conts).reverse().tmark(0@0);
  

•    var curcont := conts.fetch(0);
  

•    var tmpitem := bat(void, oid).seqbase(0@0);
  

•    var tmpkind := bat(void, int).seqbase(0@0);
  

•    conts := conts.tmark(0@0); # conts[void,int]
  

•    conts@batloop(){
  

•        # start of next container, save items|kinds of previous container
  

•        if($t != curcont) {
  

•            curcont := $t;
  

•            ritems.insert(curcont, tmpitem);
  

•            rkinds.insert(curcont, tmpkind);
  

•            tmpitem := bat(void, oid).seqbase(0@0);
  

•            tmpkind := bat(void, int).seqbase(0@0);
  

•        }
  

•        tmpitem.append(itemcont.fetch($h));
  

•        tmpkind.append(kindcont.fetch($h));
  

•    }
  

•    ritems.insert(curcont, tmpitem);
  

•    rkinds.insert(curcont, tmpkind);
  

• }

• conts := get_container([int](returned_kind)); # [oid,int]: container IDs in tail
• unq_conts := tunique(conts).hmark(0@0);
• nconts := count(unq_conts);
• rs := rangesplit(conts, nconts).tmark(0@0).reverse().join(unq_conts).reverse();

(see above)

vvvvvvvvv

• ritems := rs.[mirror]().[leftfetchjoin](const returned_item);
• ritems := [tmark](ritems, const 0@0);
• rkinds := rs.[mirror]().[leftfetchjoin](const returned_kind);
• rkinds := [tmark](rkinds, const 0@0);

^^^^^^^^^ (see above)

 # align uitems|kinds and ritems|kinds,
 # fill missing container with emtpybat
 var emptybat := bat(void,void,0);

• uitems@batloop(){

•    var err := CATCH({ritems.find($h);});
  

•    if(err.search("not found") >= 0){
  

•        ritems.insert($h, emptybat);
  

•    }
  

• }
• ritems@batloop(){

•    var err := CATCH({uitems.find($h);});
  

•    if(err.search("not found") >= 0){
  

•        uitems.insert($h, emptybat);
  

•    }
  

• }

• var usedonly := kdiff(uitems,ritems).project(emptybat);
• ritems.access(BAT_WRITE).insert(usedonly);
• rkinds.access(BAT_WRITE).insert(usedonly);
• var returnedonly := kdiff(ritems,uitems).project(emptybat);
• uitems.access(BAT_WRITE).insert(returnedonly);
• ukinds.access(BAT_WRITE).insert(returnedonly);

a) Do you need to modify these BATs later on? If not, you might want the set them read-only, again, after the insert: ritems.access(BAT_WRITE).insert(usedonly).access(BAT_READ); b) To be sure that your variables till point to the correct BATs (access(BAT_WRITE) *might* return a copy!), you should asign the result: ritems := ritems.access(BAT_WRITE).insert(usedonly)[.access(BAT_READ)];

Stefan