SRU (Search/Retrieval Using URL)

CQL: Contextual Query Language

Conformance/Base Profile

In order to claim conformance to CQL a server must support one of the following three levels:

Level 0

  1. Must be able to process a term-only query.
    (The term is either a single word or if multiple words separated by spaces then the entire search term is quoted). If the term includes quote marks , they must be a escaped by preceding them with a backslash, e.g."rai sing the \"titanic\"".)
  2. If an unsupported query is supplied, must be able to respond with a diagnostic to say that the query is not supported.

Level 1

  1. Support for Level 0.
  2. Ability to parse both:
    (a) search clauses consisting of 'index relation searchTerm'; and
    (b) queries where search terms are combined with booleans, e.g. "term 1 AND term2"
  3. Support for at least one of (a) and (b).

Note that (b) does not necessarily include queries such as:

index relation term1 AND index relation term2

but rather queries where the search clauses are terms-only (do not inclu de index or relation).

Level 2

  1. Support for Level 1.
  2. Ability to parse all of CQL and respond with appropriate diagnostics.

Note that Level 2 does not require support for all of CQL, it requires that the server be able to parse all of CQL (and respond with proper diagnostics for the parts not supported.).