1. A method in a computing system for selecting web pages, comprising: defining a set of web page attributes; for each of a plurality of web pages, automatically extracting from the web page one or more attribute values, each for one of the set of attributes; storing the extracted attribute values together with a URL for the web page in a dimensional model of the plurality of web pages, by adding a row for the web page to a fact table of the dimensional model, the added fact table row containing the URL and referencing, for each attribute for which an attribute value was extracted, a row corresponding to the attribute value in a dimension table of the dimensional model corresponding to the attribute; receiving a query specifying query attribute values for one or more of the set of attributes; processing the query against the dimensional model, by: for each of the set of attributes for which a query attribute value is specified, selecting the rows of the dimension table corresponding to the attribute that match the query attribute value; joining the selected rows of the dimension tables corresponding to the attributes for which a query attribute value is specified to the fact table to produce a join result; and generating a query result containing the URLs contained by the rows of the join result.