A Boolean Operator is a simple word that communicates search strategies to a computer. This might seem like something technical, but it's actually used very commonly. In fact, if you've ever Googled something (which, let's be honest, you have), you've technically used Boolean operators (they just added them automatically for you).
AND, OR, and NOT are the Boolean operators that you will use when searching through databases. You will also want to make sure you take advantage of other search strategies using "quotation marks", (parentheses), asterisks* and more. More information on how to use these tools is below.
These three operators allow you to combine search terms and search more efficiently
The first example will provide only articles that contain AIDS and Africa in them, which helps to narrow the focus of your search. The second brings up articles with either AIDS or Africa but not necessarily both (you might end up with articles about cheetahs). This can be useful if your topic has multiple terms that could describe it.
The third removes Africa from the results and only shows those AIDS articles that don't use the term Africa at all. Use care when using NOT as an operator. In the above example our intent may have been articles that focus on AIDS in other parts of the world, but an article about AIDS in the US that has the sentence: "AIDS was first discovered in Africa" will not show up.
In databases, you can use quotation marks to isolate a phrase. For instance, if you're looking for resources on natural selection, you'll want to conduct the search with phrase searching. If you search ["natural selection"], your results will include only resources that include the entire phrase. If you instead search for just [natural selection], your results will include the resources with that phrase, but it will also include all resources that have the word "natural" and the word "selection."
This is a powerful tool to conduct more accurate and specific searching. Using Discovery, if you search [natural selection], your search will yield 819,112 results. If you instead choose to include the quotation marks and search ["natural selection"], you will receive 77,090 results. That is 9.4% of the original results, which makes the search much more manageable and specific to your needs.
A wildcard uses the symbols ? or ! (depends on which database you're using) to search for variant spellings of a word. For example, if you're looking for something that includes the search word "color," you might like to actually search [col?r]. This will yield results for both the American spelling (color) and the British spelling (colour).
Wildcards differ between the different databases, so if you'd like to use them use the "Help" feature on the database to determine which symbol is correct to use.
Truncation is an incredibly powerful tool to use for searching. If you're studying the effect of laughter on human health, you'll likely want to get results that include "laugh," "laughing," and "laughter." To do this, simply add an asterisks at the end of the truncated word. Your search [laugh*] will yield all of the desired results.
Be aware that if you're looking for something like catastrophes, you will not want to put the asterisks too early. If you were to search for [cat*] for example, you would get a whole slew of results that were not even remotely relevant including topics such as "cats," "catalogs," "catamarans," and more. Truncation is a powerful tool, but make sure you use it carefully.
Databases store information in separate fields. Searching for Edgar Allan Poe in the Author Field will give you different results than if you search for him in the Subject field.
Databases organize information into fields like an Excel or Access datasheet. Searching for Poe in the author field will only bring up articles that he wrote. Searching in the subject field brings up all the articles about him. Below is an example of some of the different fields you might see.
This might seem like a lot, but the more that you use these tools, the more comfortable you will become with searching in this way. You'll also notice how powerful this kind of searching turns out to be.
Using these operators serves to better your search in a number of ways, and if you combine Boolean operators with advanced keyword searching and the tools above, you will get the best resources for your topic. To advance your keyword search, follow these steps:
Note: always make sure to use the correct database. A search using these limiters in Academic Search Complete will yield 0 results, but in the library science-specific database, LISTA, it will yield 44 useful results.