Intern:Keyword

Keywords can be assigned to data sets, events, parameters, staffs, institutions, and references. They generally allow for grouping records in these tables and thus can be used to produce specific selections of records. We distinguish several types of keywords:
 * Technical keywords
 * Implicite keywords
 * Free keywords

Technical keywords

 * 1) Technical keywords should be used to produce non-ambiguous selections of records. E.g. you must define a technical keyword @IMAGES for the project IMAGES, because the scope of the term images is ambiguous and therefore it is likely that you will not get an exclusive selection of records for that project.
 * 2) Characters to be used are: {A-Z,a-z,0-9} (not allowed are {-,_, ,} all special characters and umlauts etc.)
 * 3) The first character is @.
 * 4) The first character after the @ character must not be a cipher.
 * 5) Do not define keywords having only meaningless or general terms that could be used also for another context.
 * 6) Put the general terms in front, followed by more specialized terms.
 * 7) Inner capitels (Binnenkapitele) could be used for better readability of composites.
 * 8) All queries including those for technical keywords are not case sensitive. So, using capital letter, inner capitels etc. is only for our internal work with these keywords. But technical keywords are case sensitive once defined => do not define a technical keyword again with another spelling! This is important for Sets beeing harvested via OAI-PMH and distributed through specific Portals.
 * 9) The @Ref... keywords are reserved for usage by the PANGAEA system. It is an implicite mechanism that links references and data sets through these keywords.

Examples:
 * @JGOFSFrance  -> http://www.pangaea.de/search?q=@JGOFSFrance
 * @BAH2005  -> http://www.pangaea.de/search?q=@BAH2005


 * @citable -> data sets with status published & citable and supplementary data (dataStatus >= 10)
 * http://www.pangaea.de/search?q=@citable
 * @supplement  -> data sets only with status supplementary data
 * http://www.pangaea.de/search?q=@supplement
 * @citable -@supplement  -> data sets only with status published & citable
 * http://www.pangaea.de/search?q=@citable+-@supplement

Implicite keywords
There are technical keywords which automatically exist by definition and which can also be used to produce non-ambiguous selections of records. They are neither visible in the 4D editorial environment nor are they embedded in the metadata (examples with XXX=ID of related table):
 * @eventxxxxx: data sets resulting from investigations on the event with ID=xxxxx
 * Sediment core PS1768-8 has EventID=1907  -> http://www.pangaea.de/search?q=@event1907
 * @projectxxxxx: data sets belonging to the project with ID=xxxxx
 * IMAGES ProjectID=3001  -> http://www.pangaea.de/search?q=@project3001
 * @authorxxxxx: data sets of the author with ID=xxxxx
 * Eugen Seibold has StaffID=122  -> http://www.pangaea.de/search?q=@author122
 * @pixxx: data sets of a certain PI
 * Hannes Grobe has StaffID=9  -> http://www.pangaea.de/search?q=@pi9
 * @datasetxxxxx: provide me with exactly one data set with ID=xxxxx
 * this one  -> http://www.pangaea.de/search?q=@dataset126415
 * @paramxxxx: data sets including a certain parameter with ID=xxxxx (good choice when using the data warehouse)
 * all including Barium [µmol/l] ID=722  -> http://www.pangaea.de/search?q=@param722
 * @refxxxxx  -> data sets related to a certain reference with ID=xxxxx
 * Zoltai (1983) has ReferenceID=32945  -> http://www.pangaea.de/search?q=@ref32945

Free keywords
They have no syntax constraints but should currently not be used (a structured approach for a thesaurus is under construction)

Editing keywords in 4D

 * from the menu choose "View" -> "Thesaurus" - by default the list is empty
 * type in the search box the keyword that you are looking for (or any part of the string)
 * double click the keyword to get into the editing mode, edit the line
 * in case you want to define a new record, click the "new" button, type in the keyword in the empty line
 * add keyword(s) to entries in a table
 * go to the table of your choice
 * make a selection of records from the list
 * click on the button
 * select keyword(s) from the multiple choice list
 * 