---+ Results from the Berlin Protocol Meeting
---+++++ Minutes
The BerlinMeetingMinutes are available in a brief table form.

---+++++ Changes agreed in Berlin

Improvement to the SecondProposal:

   * Terminology
      * provider=host: a whole provider software installation
      * datasource=database="collection of objects": a single connected database or a datasubset e.g. visible through a view supporting different ConceptualSchemas
      * resource: a single datasource bound to a single ConceptualSchema
   * AccessPoints
      * providers supporting all RequestTypes
     * metadata response returns metadata for the provider and all its datasources
     * capabilities response returns the capabilities for all datasources
     * initially do not merge responses from several datasources, although it might be desireable in the future, esp. for inventories.
      * datasources supporting all RequestTypes
     * metadata response returns metadata for the provider and this datasource incl all "resources"=schemas with their record numbers
     * capabilities response returns capability of this datasource. that is config&request type capabilities for each resource seperately
   * Header
      * leave request <type> attribute and generically name the element following header for all requests details "message"
      * source repeatable with sequence important and the first source element being the original source
     * source element keeps resource attribute to allow to specify origin of the data. might be repeated for a response of several datasources
      * destination element repeatable to submit distributed queries to several and single providers
     * destination element keeps resource attribute to allow adressing of several datasources within a single request to a provider
      * remove compression element
      * move detailed software/components complex type to provider related capability and just keep the overall versioning with <software name="xxx" version="xyz" BerlinMeetingResults>
   * RequestTypes needed to be implemented:
      * PingRequest
      * CapabilitiesRequest
      * MetadataRequest
      * InventoryRequest
      * SearchRequest (see below)
      * *open issue:* CustomSearch needed?
   * capabilities response, see CapabilitiesProposalThree
   * metadata response, see MetadataProposalTwo
      * drop IPR, insert supported schemas incl record count
      * add logo URL
      * attach date-last-updated to resource
   * SearchRequest (see SearchProposalTwo)
      * search based on the full/partial search for a single configured ConceptualSchema
      * allows to combine several schemas for a response (to use extension schemas) by specifying a list of qualified concepts instead. See SearchProposalTwo for details.
      * always returns a valid document. in case mandatory data is missing, drop the record or branch. dont use NULLs in response.
      * when requesting no concept at all, return only the mandatory concepts.
      * request the root node of a schema to retrieve the full document
      * allow to ask for BranchNodes to implicitly request all child LeafNodes
      * sorting is not appropiate nor doable
      * specify the top level structure of the search response in the protocol with a slot for metadata and one for the content defined as records.
     * allow the response of multiple "datasets" with different metadata from a single datasource to suit the needs of databases like fishbase and systax
     * allow the
     * allow the metadata definition to be chosen by the provider and make it a mandatory part of the reponse that cannot be altered by any request. Do so for all paging and subsequent responses to the same client.
   * InventoryRequest
      * allow multiple concepts to be scanned
      * optionally request sorting of result list. order by sequence of requested concepts if multiple.
   * ConceptualBindingProposalOne accepted. OK to use namespace declaration in xml manner. Concept identifier attribute is to be called "path".
   * valid filter operators
      * Logical: AND, OR, NOT with AND + OR taking multiple arguments while NOT is unary.
      * Comparative: equals, lessThan, lessThanOrEquals, greaterThan, greaterThanOrEquals, like, in, isNull
      * There is no need for an isMapped operator.
   * Filters
      * allow search requests without filters (affects both).
      * evaluate to false if concept is not mapped but compared.
      * always insert info/warn diagnostic if unmapped concept encountered in request.
   * use common Error Codes and prefixes for classification of codes. To be specified in more detail.
   * Using a single POST or GET parameter called "request" which contains either the XML message or an URL pointing to the XML message.

---+++++ XQuery
The XqueryLanguage seems not appropiate for now, as not enough free tools are availbale and writing parsers on our own would be too much work and hard to confine.

---+++++ OpenGIS CQL etc.
   * their filters are similar, more powerful in general, but are lacking some features:
   * comparative operator IN is missing
   * functions supported
   * spatial operators supported
   * real expressions supported in comparisons that can "use" arithmetic operations, functions, literals and concepts
   * An InventoryRequest is missing

---+++++ SOAP
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