OGC 07-045
8.2.3.3 Record locking
This specification does not define a locking interface, instead relying on the underlying repository to mediate concurrent access to catalogue records.
8.2.4 Error handling
In the event that the submitted request is invalid, an exception report message is generated and returned to the client. This report complies with the definition of exception
reports that are specified by OGC Common specification see [OGC 05-008c1]. Table 39 shows an excerpt from that document that lists valid exception codes and meanings
that are supported by this profile
35
.
Table 39 - Exception codes and meanings from OGC Common
Meaning of code “locator”
value exceptionCode value
Operation request does not include a parameter value, and this server did not
declare a default value for that parameter Name of
missing parameter
MissingParameterValue
Operation request contains an invalid parameter value a
Name of parameter with
invalid value InvalidParameterValue
List of versions in “AcceptVersions” parameter value, in GetCapabilities
operation request, did not include any version supported by this server
None, omit “locator”
parameter VersionNegotiationFailed
InvalidUpdateSequence Value of optional updateSequence
parameter, in GetCapabilities operation request, is greater than current value of
service metadata updateSequence number None, omit
“locator” parameter
No other exceptionCode specified by this service and server applies to this exception
None, omit “locator”
parameter NoApplicableCode
a When an invalid parameter value is received, it seems desirable to place the invalid values in
ExceptionText strings associated with the InvalidParameterValue value.
The XML encoding of an exception has to comply with owsExceptionReport.xsd that is attached to the further mention OGC Common specification. See this document for
details.
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In future versions of this profile additional values for the exceptionCode parameter will be defined
Copyright © 2007 Open Geospatial Consortium, Inc. All Rights Reserved. 87
OGC 07-045 8.3
Query facilities
The interoperability goal is supported by the specification of a minimal abstract query predicate language, which must be supported by all compliant OGC Catalogue
Services. This query language is called OGC_Common Catalogue Query Language CQL see [OGC 07-006]. It supports nested Boolean queries, text matching operations,
temporal data types, and geospatial operators. CQL assists the consumer in the discovery of datasets of interest at all sites supporting the OGC Catalogue Services.
OGC Filter Encoding is an XML based encoding of the OGC_Common Query Language. This query language Version 1.1.0 must be supported by all catalogue instances of this
profile in order to support search interoperability. In addition, the plain textual encoding of CQL version 2.0 may be supported. The capabilities document of the catalogue
instance shall describe all supported query languages see Capabilities Document in Annex E .
The following conditions must be met by the supported query language: • support for the logical operators:
o And
o Or
o Not
• support for the comparison operators: o
EqualTo o
NotEqualTo o
LessThan o
GreaterThan o
LessThanOrEqualTo o
GreaterThanOrEqualTo o
Like o
NullCheck • support for the following expressions:
o property name
o literal
88 Copyright © 2007 Open Geospatial Consortium, Inc. All Rights Reserved.
OGC 07-045
• support for the following spatial operators
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: o
Intersects o
Disjoint o
BBOX If the value of a search parameter in a metadata entry is a missing value, then the
metadata set entry does not fulfill this search condition. Catalogue instances must ensure that the capabilities for searching tightly-coupled
services based on the queryable properties defined in table 14 is implemented see 7.2.4.
8.4 Implementation guidance
