The documents are returned sorted on relevance depending on order, proximity, frequency of terms.
Default search behavior
By default, all search terms are optional. It behaves like an OR logic. Objects that contain the more terms are rated higher in the results and will appear first in their type. For example, wiki forum will find:
- objects that include both terms
- objects that include the term wiki
- objects that include the term forum
Requiring terms
Add a plus sign ( + ) before a term to indicate that the term must appear in results. Example: +wiki forum will find objects containing at least wiki. Objects with both terms and many occurences of the terms will appear first.
Excluding terms
Add a minus sign ( - ) before a term to indicate that the term must not appear in the results. To reduce a term's value without completely excluding it, use a tilde. Example: -wiki forum will find objects that do not contain wiki but contain forum
Grouping terms
Use parenthesis ( ) to group terms into subexpressions. Example: +wiki +(forum blog) will find objects that contain wiki and forum or that contain wiki and blog in any order.
Finding phrases
Use double quotes ( " " ) around a phrase to find terms in the exact order, exactly as typed. Example: "Alex Bell" will not find Bell Alex or Alex G. Bell.
Using wildcards
Add an asterisk ( * ) after a term to find objects that include the root word. For example, run* will find:
- objects that include the term run
- objects that include the term runner
- objects that include the term running
Reducing a term's value
Add a tilde ( ~ ) before a term to reduce its value indicate to the ranking of the results. Objects that contain the term will appear lower than other objects (unlike the minus sign which will completely exclude a term). Example: +wiki ~forum will rate an object with only wiki higher that an object with wiki and forum.
Changing relevance value
Add a less than ( < ) or greater than ( > ) sign before a term to change the term's contribution to the overall relevance value assigned to a object. Example: +wiki +(>forum < blog) will find objects that contain wiki and forum or wiki and blog in any order. wiki forum will be rated higher.
SAFE OGC Metadata Mapping
Dear All,
Please, find attached the excel table with all the metadata mapped/not mapped from SAFE 1.3 and SAFE 2.0 (presented at PDR-C) to OGC.
Three tabs have been created in the excel file:
- SAFE Metadata mapped to OGC: SAFE metadata that have been mapped to OGC. These are candidates to be dropped from the Core Document (because they are already part of OGC EOP O&M).
- SAFE Metadata not mapped to OGC: SAFE metadata that have not been mapped to OGC. These are the candidates to be included in the Core Document (SAFE-OWN extension).
- QA4EO Metadata: Metadata aligned with QA4EO. The decision of adopting or not these metadata (in SAFE 2.0) is still pending to be confirmed after further analysis of the ESA PDGS Catalogue Metadata.
For the sake of simplicity, we have decided not to provide detailed information for each metadata mapping. We think that this would help you to track easily the metadata elements.
Any comments are welcome.
Thank you very much.