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Boolean logic operators

Boolean logic operators (named after the nineteenth century British mathematician and philosopher, George Boole) are used to construct search queries with higher precision.

FSTA Direct supports the three main Boolean logic operators:

• AND
• OR
• NOT

These operators are used to combine individual search terms. Quotation marks (" ") are used to specify an exact phrase. If no operator is specified then AND is assumed.

Examples

• term1 AND term2 will find records with both terms present
• term1 term2 is interpreted as term1 AND term2
• "search phrase 1" AND term2 will find records with the phrase and second search term present
• "search phrase 1" term2 is interpreted as "search phrase 1" AND term2
• term1 OR term2 will find records with one or both terms present
• term1 NOT term2 will find records where term1 is present and term2 is absent

If two or more words appear without parentheses or Boolean logical operators present then an AND search is performed.

See also