Search Skills: Boolean Searching

Boolean searching is based around three functions, called operators, that combine keywords .

 AND 

When keywords have AND between them:

• All keywords must be in the source's record .
• AND makes a search smaller.
• Use AND between each concept or part of your search.

 OR 

When keywords have OR between them:

• The source's record may have any combination of the keywords.
• It may match on one, some, or all of the keywords.
• OR makes a search larger. 
• Use OR between each synonym within a concept.

 NOT 

When keywords have NOT between them:

• The keyword after the NOT can't appear anywhere in the source's record. 
• Use NOT when a word is used in two very different contexts. 
• Use NOT when you want everything in a topic except one subtopic, as it is shorter than using many words with OR.
  • For example, if you were trying to research seizure disorders that aren't epilepsy, it would be faster to add NOT epilepsy than list all the other possible disorders.

Most Library databases will have multiple search boxes in their advanced search. This makes combinations of OR and AND easier.

Example:The LopeSearch (EBSCO)

• Put keywords with OR in the same search box.
• Put keywords with AND in different boxes. 

These two habits will let you adjust your search faster.

While most of the Library databases will start with three boxes, you can add more or not use them all depending on your search.

Example Search:

From our topic on bullying this might become:

AND

AND

AND

Hover your mouse (tab, or tap on mobile) over the Boolean operator to see the different effects in the Venn diagram.

Library subscription databases do not search the full text of an article by default. Instead they search on the record, the information about the article or book. 

Database records usually include:

• The publication information such as:
  • Title.
  • Author.
  • Publication.
  • Date.
  • DOI if there is one.
• Subjects or Keywords.
  • These may be assigned by the database or provided by the author.
• Abstract .

For example, in a typical EBSCO record you will find:

1. Article Title.
2. Authors.
3. Publication information, including the journal title, date, and issue, under "Source".
4. Subjects.
5. Keywords.
6. Abstract.
7. The DOI, if there is one.

When you enter keywords into a database search, these fields are where the search looks for a match. Most databases can search the full text of articles in the database, but you must change a setting for your search to do so.