Search Strategies: Tips for Working with Databases: Boolean Operators

Using AND in your search:

• Narrows, or decreases, the number of results in a search.
• All terms entered with AND will be present in the resulting records

Here's a visual representation of this example: video games AND violence AND children. The middle triangle, a smaller set of results, will be returned using the search terms with AND.

Using OR in your search:

• Broadens, or increases, the number of results in a search.
• Any term entered with OR will be present in the resulting record.
• Use OR to group synonyms together

Here's a visual representation of this example: aggression OR bullying OR violence. This expands the results so that all records with any of the search terms is returned.

Using NOT in your search:

• Narrows, or decreases, the number of results in a search.
• Excludes word or phrase following NOT from the result list.

Here's a visual representation of this example: video games NOT Halo. The results list only returns records with video games, but not about the video game Halo.

Here's a quick video from McMaster University that will explain more about Boolean Operators.

Now, learn how to format your search for even better results.