Oracle ATG Web Commerce Search has a number of data structures that can be used to organize an index. These structures make it possible to restrict searches to specific portions of the index.
When you specify a metadata property in the definition file, you can use one of the following Boolean attributes to specify how to structure the index based on the values of the property:
store-as-meta-index-- Iftrue, the value of the property is used as a key in a lookup table, to enable rapid retrieval of the document. This option should be used only if each value of the property is unique. For example, theProductCatalogOutputConfigcomponent is configured by default to usestore-as-meta-indexfor the$repositoryIdproperty of theproductitem. Since each repository ID is unique, if a query includes a constraint that specifies the$repositoryIdvalue, the correct product can be retrieved by lookup without searching the entire index.store-as-docset-- Iftrue, the output documents are stored in a document set whose structure is based on the values of the property. This makes it possible to restrict searches to only specific locations in the index. For example, the category navigation feature used in faceted search depends on category IDs being stored as a document set. See the ATG Search Query Guide for information about category navigation.store-as-collection-- Iftrue, a collection is created for each value of the property. This option is particularly useful for a product catalog repository that has a large number ofcatalogitems (for example, for business-to-business commerce). See Indexing a Large Number of Catalog Items.
