The Query Accelerator is a mechanism for optimising selected queries in very large content repositories. We would suggest using this feature to support large transactional deployments with hundreds of millions of nodes, where documents are automatically imported from other systems, rather than traditional collaborative content management system where humans are creating documents. In transactional deployments there typically is a case id and one or two other properties, which identify a related collection of documents.
An administrator may define a combination of properties and aspects as a query set, to support a faster alternative to Transactional Metadata Query (TMDQ) or Solr. Properties may be from multiple types or aspects. A single query set can speed up more than one query if the queries share common search properties or aspects. A number of different query sets may be created to support queries with different search properties or aspects.
This performance comes at the cost of additional space for denormalized databases tables and indexes as well as a minimal increased time on ingestion and update. This will however allow customers to make that decision. Having many properties in a query set or having lots of query sets should be avoided, as the cost will be high and generally indicates that there is something wrong with the data model design.