In database systems, a search query in which more than one word can be searched for at one time. Each term is connected by Boolean operators such as "and," "or," and "not." In a Boolean search (which is based in principles of Boolean algebra), two or more search criteria may be used at one time in three logical relationships. For example, to find "giant squid" you could choose "giant" and "squid." In this case, a text string will qualify as a "hit" if it contains both those words. Searching for "giant" or "squid" would yield all text striungs containing "giant," and all text strings containing "squid." All text strings containing both terms will also qualify as "hits." A third alternative would be "squid" not "giant," and "hits" will pick up all text strings containing "squid" but not "giant."