If any Boolean operator
is not used in search, then pubMed will automatically use AND" between terms.
The students explore Boolean matching by writing and executing simple Boolean queries: pairs of elementary queries (terms) connected by a single Boolean operator
(OR, AND), or a pair of operators (AND NOT), which simulate set difference.
Compare the effects of the use of the Boolean operators
AND and OR.
XOR Boolean operator
presented here uses the standard Boolean operators
OR, AND, and NOT as follows:
Under the conventional interpretation, the input to a Boolean operator
is either 0 or 1.
On the help page, users are advised that Boolean operators
do not work with this search engine.
Use Boolean operators
and field qualifiers to build a search strategy from base URL
Caution for experienced searchers is required when encountering BUBL keyword searching, for unlike many CD-ROMs which have the AND operator as the default operator, the Boolean operator
OR is the default search operator on BUBL.
CD-ROM Version Software features: Full-text Search with Boolean operator
A Boolean operator
menu determines how search terms are connected.
Software features: Full-text Search with Boolean operator
support Keyword Indexes: Comprehensive Index, Trade Name X-Ref, Generic Chemical X-Ref, Manufacturers X-Ref, CAS X-Ref, EINECS/ELINCS X-Ref, Functional/Applications X-Ref.
We plan to improve the search functionality by incorporating Boolean operators
and exclusively utilizing tags applied to each topic, allowing more refined searches based on multiple symptoms.
Table1: Boolean Operators
Operator name and meaning Example negation (non) -[phi] conjunction (and) ([phi] & [PSI]) disjunction (or) ([phi] | [PSI]) implication (if .
Putting together search queries that incorporate fields, geolocation elements, Boolean operators
, and nested logic should make non-information professionals sit up and take notice.
Provides advanced search options such as field searching, Boolean operators
, proximity searching, nesting, wildcard/truncation, etc.