Boolean operator

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The 16 Boolean operators with 2 variables

A Boolean operator ( English Boolean operator ) is a logical operator so an operator which in truth values operated on. It is named after George Boole . The most important application area of ​​the Boolean operators is programming . A mathematical specification of the theory of Boolean operators was formalized in the concept of Boolean algebra . There the Boolean operator acts as a link on a mathematical structure . Symbols are assigned to individual Boolean operators. This is used to clearly display a logic circuit - a combination of networked Boolean operators - and to derive the associated truth table .

Boolean operators are used, for example, in programming. The most common of these operators are the AND (conjunction), OR (disjunction), NOT (negation) and XOR (exclusive OR ) operator . Boolean operators are used, for example, in query languages , such as in the SQL expression

  SELECT * FROM Customers
  WHERE Country='Germany' AND City='Berlin';

with which all entries are selected from the Customers table that have Germany as the value for the Country column and Berlin as the value of the City column. Such a search procedure is also called a Boolean search procedure .

The NAND and NOR operators are also important operators in digital technology .

See also

Individual evidence

  1. ^ Boolean algebra . In: Ramesh Bangia (Ed.): Dictionary of Information Technology . 2nd Edition. Motilal UK Books of India, 2010, ISBN 978-93-8029815-3 .
  2. ^ Boolean operator . In: Ramesh Bangia (Ed.): Dictionary of Information Technology . 2nd Edition. Motilal UK Books of India, 2010, ISBN 978-93-8029815-3 .