Browse Benchmarks

Benchmark ::simple_aggr : Corelated nested query in the let clause and with aggregate function in the return clause
(submitted at 2006-11-24)
Authors: Norman May (University of Mannheim)
Categories: XQuery,
Target: All systems
Engine type: persistent-storage main-memory
Measure: The measure targets the total execution time.
Result unit: Milliseconds

Query:
The naive evaluation of this query evaluates in nested-loops. This results in a quadratic increase in excution time when the document size is increased. More efficient evaluation strategies scale better.
Syntax: for $t1 in distinct-values(doc("prices.xml")//book/title) let $p1 := for $p2 in doc("prices.xml")//book [title eq $t1]/price return decimal($p2) return <minprice title="{ $t1 }"> <price> { min($p1) } </price> </minprice>
Language: XQuery 1.0

Document:
The document creates a document that conforms to the DTD used for the XQuery Use Case REL.
Generator: Toxgene and reldata.tsl

Parameters:
Parameter num_items:
the number of items, this is the main scaling parameter
This parameter characterizes the: doc
Unit: None.
Values: 100 1000 10000
Distribution: uniform
Scale: ordinal
Parameter num_bids_per_item:
The number of bids per item.
This parameter characterizes the: doc
Unit: None
Values: 10
Distribution: uniform
Scale: ordinal

Methodology:
Running scenario: queryScale
Test the influence of the document size (which depends on parameter num_items) on the query execution time.
Parameter instantiation:
Name Value(s)
num_items 100 , 1000 , 10000
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