Difference between revisions of "GCQLParser"
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| − | == | + | ==Contextual Query Language== |
Contextual Query Language (CQL), previously known as Common Query Language, is a formal language for representing queries to information retrieval systems such as search engines. Its design objective is that queries be human readable and writable, and that the language be intuitive while maintaining the expressiveness of more complex query languages. | Contextual Query Language (CQL), previously known as Common Query Language, is a formal language for representing queries to information retrieval systems such as search engines. Its design objective is that queries be human readable and writable, and that the language be intuitive while maintaining the expressiveness of more complex query languages. | ||
The specification of the language as well as usage examples can be found [http://www.loc.gov/standards/sru/specs/cql.html here]. | The specification of the language as well as usage examples can be found [http://www.loc.gov/standards/sru/specs/cql.html here]. | ||
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| + | ==CQL enhancements== | ||
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| + | In the context of the gCube framework, certain enhancements have been applied on CQL, in order to enable necessary functionalities of the [[Search_Framework_2.0]]. More explicitly, two additional keywords are used: | ||
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| + | * '''project''': allows the user to determine the fields that she needs to be selected for projection. | ||
| + | * '''fuse''': if used enables the fusion of the results coming from different [[Data Sources]]. | ||
Revision as of 09:21, 11 October 2013
Contextual Query Language
Contextual Query Language (CQL), previously known as Common Query Language, is a formal language for representing queries to information retrieval systems such as search engines. Its design objective is that queries be human readable and writable, and that the language be intuitive while maintaining the expressiveness of more complex query languages.
The specification of the language as well as usage examples can be found here.
CQL enhancements
In the context of the gCube framework, certain enhancements have been applied on CQL, in order to enable necessary functionalities of the Search_Framework_2.0. More explicitly, two additional keywords are used:
- project: allows the user to determine the fields that she needs to be selected for projection.
- fuse: if used enables the fusion of the results coming from different Data Sources.
