On Thu, May 24, 2007 at 05:07:03PM +0200, Maarten Clements wrote:
Using the following XQuery in MonetDb (WinXP) crashes on large documents
the usual questions: 1) which version of MonetDB XQuery are you using? 2) what exactly does "crash" mean? does the Mserver simply stop? Is the any error message? Does Mserver grow/excessively use resources before crashing? ...? 3) what does "large" and "small" mean wrt., your document sizes? (serialized file size in byte? number of /collection/doc nodes in either document? ...?) 4) how much memory does your machine have?
(when C1 and C2 are small it works ok):
<col> { for $b in doc("C1.xml")/collection/doc for $top in doc("C2.xml")/collection/doc where ($b/year > 1950) and ($b/title = $top/title) return <movie> {$b/year} </movie> } </col>
If I remove one of the two conditions it works perfectly, e.g.:
<col> { for $b in doc("C1.xml")/collection/doc for $top in doc("C2.xml")/collection/doc where ($b/title = $top/title) return <movie> {$b/year} </movie> } </col>
Can anyone explain this problem?
most probably, the more complex join condition is not recognized as join, then the intermediate result (corss product) blows up. Stefan
______________________________ Maarten Clements
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