=Paper=
{{Paper
|id=Vol-1189/invited_paper_3
|storemode=property
|title=Logical Approaches to Query Optimization over Web-Based Sources
|pdfUrl=https://ceur-ws.org/Vol-1189/invited_paper_3.pdf
|volume=Vol-1189
|dblpUrl=https://dblp.org/rec/conf/amw/Benedikt14
}}
==Logical Approaches to Query Optimization over Web-Based Sources==
<pdf width="1500px">https://ceur-ws.org/Vol-1189/invited_paper_3.pdf</pdf>
<pre>
Logical approaches to query optimization
         over web-based sources

                           Michael Benedikt

        Department of Computer Science, University of Oxford
                 michael.benedikt@cs.ox.ac.uk



Abstract. Much of the data needed to answer user queries resides on
the web – accessible via web apis or web forms. The setting is answering
queries over sources that are connected to one another by semantic rela-
tionships (that is, integrity constraints). The sources may have overlap,
may have multiple means of access with different requirements (e.g. num-
ber of required arguments), and the means of access within and across
relations may differ radically in cost. This work presents a method for
generating query plans that run on top of these sources, obeying the
access patterns and exploiting the integrity constraints. The approach is
based on ”implementing” interpolation and definability results in predi-
cate logic, while extending them to take into account access restrictions,
modifying them work in the presence of background integrity constraints,
combining them with cost considerations. In this talk I will give a flavor
of the theory behind the logic-based approach, and then discuss a vari-
ety of algorithmic and system issues. This is joint work with Balder ten
Cate, Julien Leblay, and Efi Tsamoura.

</pre>