Specific Searching with Boolean
AbeBooks' Boolean search allows you to perform very specific searches. It's based on a mathematical logic but is actually simple to use. Boolean logic helps you to expand or restrict your search. Boolean has three so-called operators (commands to our search engine) – NOT, AND, then OR.
NOT is given the highest precedence in Boolean, followed by AND, and then OR. If you have two Boolean operators in one search, the search will use the order of precedence.
- Always remember to turn on Boolean first by clicking the radio button.
- You always need a positive term to precede any operator in the field when using Boolean. This is the most common error. For instance, after putting J.K. Rowling into the author field, a title search would be – The Philosopher's Stone NOT The Sorcerer's Stone
- Be aware quotation marks around search terms will indicate an exact phrase and ensure even stricter searching. The terms entered will be matched exactly. This can be good and bad. An "Ernest Hemingway" author search will yield exactly that and not any books where the author is listed as Hemingway, Ernest.
- The keyword field is extremely useful for Boolean searching because it searches all fields for data (author, title, publisher, description etc).
Examples of Common Boolean Searches:
- Example 1 – Exclude ex-library copies using the NOT operator.
Enter a positive term(s) into keyword field eg J.R.R Tolkien, The Hobbit NOT ex-library NOT ex-libris.
- Example 2 – Exclude a certain publisher using the NOT operator.
Enter a positive term into publisher field eg Bloomsbury and then enter NOT Scholastic.
- Example 3 – Two books in one search using the OR operator.
Complete author field (eg Ian McEwan) and then complete title field Atonement OR Amsterdam. Two separate searches will occur but your results will combine both sets of results.
- Example 4 – Expand a search with multiple OR operators.
You want books about war. Enter into keyword field war OR military OR battle OR warfare OR combat.
Invalid Searches include:
- Keyword search (lacks negative term): Cat not
- Author search (cannot have successive operators without a search term): Stephen or not King
- Title search (lacks positive term): not The Shining
Be careful when using Boolean and searching for titles/keywords containing 'and', 'or' & 'not'. For instance, searching for Hemingway's famous books, To Have And Have Not and The Old Man And The Sea, can cause problems as Boolean will recognize the operator words contained within the titles. Avoid this problem by putting the titles in quotation marks – "To Have And Have Not" OR "The Old Man And the Sea" - you will be presented with both titles in a combined set of results.
To group a series of words together, use parentheses which will string a series of terms together and properly categorize your results. For example a keyword search of (Khaled Hosseini NOT "A Thousand Splendid Suns") OR (Ernest Hemingway NOT "Old Man and the Sea"). Parentheses are also be used to force the order of processing.