How to search
There are four ways of searching the portal: manual search, advanced search, SPARQL search and graph search.
Manual search
Boolean operators
General Remarks
You can search for datasets containing one or more keywords by typing the keywords into the search field and then clicking on the search button. When entering more than one search term it is also possible to use the logical operators (connectors) AND, OR as well as parentheses (). The concepts behind and rules for using logical operators and parentheses are briefly explained in the following sections.
Concepts of logical operators and parentheses
Logical Operator OR
The OR operator can be used in order to
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connect two or more similar concepts (synonyms)
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broaden your results, telling the database that ANY of your search terms can be present in the resulting dataset
Example: population OR education OR science
All three circles represent the result set for this search. It is a big set because any of those words are valid using the OR operator.
Logical Operator AND
The AND operator is used to
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find sources containing two or more ideas
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narrow the search
The database will only retrieve items containing both keywords. The AND operator can be used multiple times in one query.
Example: population AND education AND science
Parantheses ()
Parentheses is used to
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perform a more complex search using both AND and OR by placing parentheses around synonyms
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save time by searching multiple synonyms at once
Example: (environment OR nature) AND (refurbish OR reuse)
This cuts down on having to perform multiple searches for the combinations on keywords.
Basic rules for using AND, OR operators and parentheses ()
The OR is implied: search function automatically puts an OR in between your search terms. It means that the search for population OR education OR science gets the same matches as the search for population education science.
Always enter AND, OR operators in uppercase letters.
Never translate AND, OR operators into any other language. It does not matter in what language your keywords are -- the operators always have to be AND, OR.
Please keep in mind to always close parentheses (). The combination of logical operators with an odd number of parentheses in the query leads to incorrect results in the search.