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Search operators

With HPB you can modify your query in such a way that you search for a specific subject, publication or author. Using Boolean, wildcard and proximity operators you can modify a general query so that the search more closely approximates your expectations.

Descriptions of the search keys available from the drop-down menus can be found on Simple Search help page. An extensive documentation of all available search keys is available on this separate help page

Search using search operators

HPB supports the following search operators:

Target of your search: Please select:
All search terms must occur in the title ALL
One or other of the search terms must occur in the title OR
A particular term must not occur in the title NOT
The search terms must be near to each other NEAR
Search for a Phrase, i.e. an exact word sequence "Phrase"
The terms must occur in the specified order. There can be … terms between the search terms: any number - maximum one term - exactly one term - no terms
You don't know the exact spelling of the key term or name Wildcards

Boolean operators

If your search query is too generalised you may receive an unmanageable number of hits, or too few if the search term is too specific. To achieve better results, you can use Boolean operators in your search.

Operator Example Explanation

house garden
house and garden
house & garden
+house +garden
Searches only for titles containing both terms specified.
or house or garden
house | garden
Searches for titles containing either the term house house or garden or both terms.
and or (car or vehicle) and (transport or traffic) If you want to search for several topics combined that can be expressed through various terms, you can use the and and or operators together. Here it is important, however, to put brackets around terms linked with orwhich represent the same topic. This then searches for entries that contain at least one of the terms within each pair of brackets.
house not garden
house -garden
Titles searched must always contain the term house but never the term garden.

house near garden
house ~ garden
house near/3 garden
This searches for titles in which there are a maximum of 3 words between the search terms, e.g.
garden, house courtyard
house with a garden
A house with a magnificant garden
Enter near/3 to specifiy that there can be a maximum of 2 words between the search terms.
“…“ “freedom as duty” Searches only for titles containing the phrase between the quotation marks. Searches for this exact word order and no other terms must appear within the phrase. This search will find, for example:
Freedom as duty of the citizen but not Freedom and unity as duty

Proximity operators

You can use proximity operators to specify whether the phrase you are looking for should be searched in the specified word order or with terms in between.

Operator Example Explanation
history ? railways
history * railways
If you separate two search terms with * or ?, the search looks for titles in which the terms occur in this order. There can be none or any number of other terms in between them. The search example finds:
History of the railways
History of the Indian Railways
# history # railways Searches only for titles containing the terms in this order. There can be a maximum of one word between the terms.
! history ! railways Searches only for titles containing the terms in this order. There can be exactly one word between the terms, e.g. history of the railways
% history % railways This operator searches for keywords in any order. There must be no other term between the search terms. The search example finds: The great railways - history and background

history %! railways Combining the % operator with one of the unidirectional operators described above (? * # !), turns them into bidirectional operators, i.e. the specified terms are searched for in any order with none or one or many terms between them. The search example finds:
history of the railways
The Great Western Railway : History of a great railway company


You can use wildcards when you are not sure how to spell a search term or you also want to search for similar terms in the same search. Wildcards can be placed at the end or in the middle of a term, but never at the beginning.

Wildcards Example Explanation
TIT fa?r The question mark acts as a wildcard for any number of characters.
Finds titles containing the keywords far, fairy, father, faster etc.
PER ha?mann At the end of a search term it works as truncation. Finds people with the name Hamann, Hagmann, Hartmann, Habermann etc.
# TIT fa#r The hash sign stands for a maximum of one character. Finds titles containing the keywords fair and far, but not father, faster etc.
..PER ha#mann finds people with the name Hamann, Hagmann and Haumann but not Hartmann or Habermann
! TIT fa!r The exclamation mark stands for exactly one character. Finds titles containing the keyword fair, but not far, father, faster etc.
ha!mann finds people with the name Hagmann, Haumann, but not Hamann, Habermann etc.
? * # ! micro!p* Wildcards can also be combined with one another within a search term. The search example finds matches with the keywords microsphere, micro-optics, microspectrophotometry
/n moskau/2 /n is not a wildcard but has a similar function: end a term with a forward slash and then add the number of characters within the search term by which a term can differ. The search example finds Moskau and Moskva and Moskou

Reserved words

All the operators used in searches are reserved words. The system understands operators entered in both German and English:

and - or - not - near
und - oder - nicht - bei

Problems arise when you run a search using search terms that match one of these operators. If possible, you should omit these terms altogether or enclose them in quotation marks or “neutralise” using a backslash.

For example, if you are searching for a title with the keywords Money or Life, the system interprets this as a search for the term money OR the term Life and returns titles that contain one or the other term. Or if you try searching for the title Not fish not meat, the system understands the word NOT as an operator and searches for titles that contain neither one nor the other term - which in this case provokes an error message.

However, if you do want to use expressions that contain the reserved words, then you must either enclose them in quotation marks or neutralise them with a backslash, e.g.

Money "or" life
money \or life
fish "not" meat
fish \not meat

Parentheses: nesting multiple search operations

You can also use parentheses in a query. Without parentheses, a query is performed according to the hierarchy of the search operators. That is, the operator that is highest in the hierarchy takes precedence. Proximity operators have the highest position in the hierarchy, followed by AND and then OR. Parentheses ensure that this hierachy is ignored. This enables you to nest your search operations.
For example: (auto OR bicycle) AND (transport OR highway) finds titles that contain auto and/or bicycle and that also include transport and/or highway.

Combining Search operators: Examples of complex search operations

It is possible to compose complex queries by combining search operators such as Boolean, wildcards and proximity operators.

  • Example 1: complex query
    NOT johann ? bach searches for titles that contain the word bach not preceded by the word johann. This search operation will not find a title containing johann sebastian bach, because in this title johann precedes bach. This search operation will find the title wilhelm bach, johann bach because the title contains an occurrence of bach not preceded by johann.
  • Example 2: complex query
    Einstein ##! gravity searches for titles that contain einstein and gravity with three or less intervening words. The query einstein NEAR/3 gravity searches for titles that contain einstein and gravity (or gravity and einstein) with three or less intervening words.
  • Example 3: complex query
    Einstein #### gravity finds titles that contain einstein and gravity with four or less intervening words. Another possibility for finding the same result is: einstein #/4 gravity.

Articles, prepositions and other fill words

Every word in a title is indexed with the exception of fill words. Fill words are words that are ignored during a search to prevent irrelevant information from being displayed. Articles, pronouns, adjectives, adverbs and prepositions are examples of fill words. Words that appear, but have no relevance during a search. For example: the, him, a, of, in, etc. FIXME check

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 help/hpb/search_operators.txt · Last modified: 2015/11/05 18:50 by kittelmann



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