Field

Only the best field in which a match occurs is considered. The Field module is often used in relevance ranking strategies for catalog applications, because the category or product name is typically a good match. Field assigns a score to each result based on the static rank of the standard or managed attribute member (or members) of the search interface that caused the document to match the query. Static field ranks are assigned based on the order in which members of a search interface are listed in the search interface configuration. The first member has the highest rank.

By default, matches caused by cross-field matching are assigned a score of zero. The score for cross-field matches can be set explicitly in the CROSS_FIELD_RELEVANCE_RANK attribute of the SEARCH_INTERFACE element. This element is used only for search interfaces that have the Field module and are configured to support cross-field matches. All non-zero ranks must be non-equal and only their order matters.

For example, a search interface might contain both Title and DocumentContent standard attributes, where hits on Title are considered more important than hits on DocumentContent (which in turn are considered more important than cross-field matches). Such a ranking is implemented by assigning the highest rank to Title, the next highest rank to DocumentContent, and setting the CROSS_FIELD_RELEVANCE_RANK attribute to a low integer such as 0 or 1.

The Field module is only valid for record search operations. This module assigns a score of zero to all results for other types of search requests. In addition, Field treats all matches the same, whether or not they are due to query expansion.