Off The Shelf

Nesting.  Nope, not the kind that birds make.  The nesting I’m talking about is used to control how the database treats your search terms when you’re building your search in a database or online.

By now you have probably heard of the Boolen Operators: AND, OR, and NOT.  These connectors are used between your keywords to tell the database how you want to combine your words and what kinds of terms should be present in your search resuts.  But what happens when you need to use different connectors (maybe a combination of ANDs and ORs) in one search box?  You need to “nest” your terms!

Nesting involves putting parantheses around like concepts to keep them together.  These parantheses are also code for the database to perform the command that’s inside of the parantheses first before adding what is outside of the parantheses, just like in math equations.  Take this search for example:

alcohol AND (adolescents OR teenagers) 

With this search the database will retrieve articles on alcohol AND adolescents or alcohol AND teenagers.  Without the parantheses the database takes your search terms literally and will search for your terms in the order you type them.  For instance, if you removed the parantheses from the bolded example above, you would find articles on alcohol and adolescents as well as articles on teenagers (without the alcohol aspect).

And sets of parantheses can be nested inside other sets of parantheses, like russian nesting dolls. 

(Alcohol OR drug OR (substance N3 abuse)) AND (teenagers OR adolescents)

Remember, the command inside the inner-most parantheses always gets processed first.

Nesting your terms comes in particularly handy when searching online in search engines like Google.  Google does recognize Boolean Operators like ANDs and ORs and will obey search commands like using parantheses in your search!  By nesting your search terms, you are better able to control how Google handles your search terms.  And when you’re searching millions upon millions of information sources, every little bit helps.   Next time you’re searching in Google, try nesting your terms and see how your search results change!

If you would like further explanation on how nesting works in the databases or online, give us a call in the library and we can walk you through how to effectively use this concept.

–Jennie