We have been experimenting with the MonetDB/XQuery at our institure and we have some issues.
We have loaded 727 XML documents into MonetDB with the shred_doc() command:
shred_doc("{xml file 1}, "1") shred_doc("{xml file 2}, "2") etc...
These files are small (4 a 5 kilobytes).
When we query these files with the following query the result takes a long time to complete (2 minutes):
for $i in ("0", "1", .... "727") return $i
Can anyone explain why looping over 727 documents is so slow? We have collected all 727 XML documents into 1 XML file and loaded this in MonetDB and this is a lot faster.
The test machine is a 2.8 GHz P4 with 1 GB of memory.
Another isue is related to the size of the database on the harddisk. When we fist load the 727 XML documents into the database the database directory contains about 47.000 files and is 50 megabytes in size. When we have excuted a number of querys the size of this directory increases to 1.7 gigabytes!! Can anyone explain this behaviour? Is MonetDB generating somekind of dynamic indices?
Thanks for your replys, Bastiaan Naber