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EMBA 117: Search Techniques

Resource Help for EMBA 117: Chill Hound

Boolean Logic Intro

Boolean Logic refers to the words " AND, OR, NOT" and their intended usage with manipulating databases to either add, include, or subtract populated information from a data set. In other words, Boolean Logic refers to the logical approach (AND) instead of the arithmetical approach (+) to retrieve information from any database that contains data sets. The arithmetical approach refers to using symbols to convey addition as opposed to the logical sense which uses words.

The importance of using Boolean Logic when searching through databases is that it allows you to have control over what information the database will populate through your search in order to increase the efficiency and relevancy of your results.

Below you will find examples of each of the instances when you would use Boolean Logic and the results they would generate. 

"AND"

When a researcher such as yourself includes the Boolean operator "AND" into a database search field box, you may assume that because of the definition of the word "and" meaning adding together, you may get back more populated results.

This is a wrong assumption to make, in reality, using the Boolean operator "AND" will actually populate less data but the data populated will be more refined. Using the "AND" Boolean operator will tell the database to search for any information that contains ALL of the search criteria. For example, searching in a database for the terms (Ducks AND Geese) will populate information/articles that ONLY contain BOTH Ducks AND Geese

Below is an example of the number of search results populated by entering "ducks AND geese" into the search field in the database Academic Search Complete powered by EBSCOhost. Compare these results with the results of "OR" and "NOT" in the sections below. 

To get to the Academic Search Complete database click on the link at the bottom of this section or review the Getting Started section located in the navigation bar on the left of the screen.

 

"OR"

Another also very common Boolean Operator is  "OR". "OR" is often used when you want as much information as possible from the two inputted search terms regardless of other words those inputted search terms might be connected too. 

In the same manner that the Boolean Operator "AND" may be confusing to beginners, "OR" has a similar misconception. Most individuals believe when we use "OR" that we want one search term or the other but not necessarily both. The truth to "OR" as an operator is that databases will populate data that contains either search term or both. Look to the ven-diagram at the top of the page to see how using "OR" will populate data. For example, searching in a database for the terms (Ducks OR Geese)  will populate information/articles that contain either ducks, or geese, or both. 

Below is an example of the number of search results populated by entering "ducks OR geese" into the search field in the database Academic Search Complete powered by EBSCOhost. Compare these results with the results of "AND" and "NOT". 

To get to the Academic Search Complete database click on the link at the bottom of this section or review the Getting Started section located in the navigation bar on the left of the screen.

 

"NOT"

Finally, our last Boolean Operator that we will be covering is "NOT". "NOT" is an operator designed to exclude a search term in order to help refine the data pulled from a database. Most of the time, using the operator "NOT" will help reduce the number of records and data pulled from a database. This is helpful when trying to limit the populated data or to make sure the database doesn't confuse your term with another similar term. For example, searching in a database for the terms (Ducks NOT Geese) will populate information that contains the search term Ducks but will omit those that contain the search term geese. This is helpful when you only want information about ducks and not about geese even though both species are related to each other. 

 

Below is an example of the number of search results populated by entering "Ducks NOT Geese" into the search field in the database Academic Search Complete powered by EBSCOhost. Compare these results with the results of "AND" and "OR". 

To get to the Academic Search Complete database click on the link at the bottom of this section or review the Getting Started section located in the navigation bar on the left of the screen.