eCOIN Demo for Global Comparison Aggregator

  Metadata:   [ Text Interface | Ontology | Context | Source | Graphical Viewer | Internal Representation ]
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  Queries
Description

This query aggregates data from all sources, which have the following contexts:
  • US sources list prices in USD, base price; domestic shipping is 50, international is 100;
  • UK sources list prices in GBP, VAT included (17.5%); domestic shipping is 10, international is 35;
  • Swedish sources list prices in SEK, VAT included (25%); domestic shipping is 20, international is 800;
  • French sources list prices in Euros, Tax included (19.6%); domestic shipping is 15, international is 80.
Receiver can be in any above stated contexts. In addition, a receiver could be in any contry and interested in price in terms of cost. For example:
  • A US buyer needs to pay 3% import tax plus international shipping if the sellers are outside USA. Appropriate shipping changes apply.
  • A UK buyer pays VAT even if the item is imported, but there is no extra import tax.


SQL
Context
Stage
Naive Datalog SQL Translation
Context Sensitive Datalog Execution
Conflict Detection
Mediation
Result
 answer('V2', 'V1'):-
	hzshopper('V2', 'V1').

answer('V2', 'V1'):-
	hzshopper2('V2', 'V1').

answer('V2', 'V1'):-
	hzpricerunneruk('V2', 'V1').

answer('V2', 'V1'):-
	hzpricerunnersweden('V2', 'V1').

answer('V2', 'V1'):-
	hzkelkoofrance('V2', 'V1').

answer('V2', 'V1'):-
	axpricerunnerdenmark('V2', 'V1').

answer('V2', 'V1'):-
	axkelkooitaly('V2', 'V1').

answer('V2', 'V1'):-
	axmysimongermany('V2', 'V1').


gcms@mit.edu