Category Archives: Boolean 101

Boolean Search Does Not = Internet Search

If you read certain sourcing and recruiting blogs and discussion groups, you might get the impression that Boolean search pretty much equals Internet search – such as searching for people and profiles using Google, Yahoo, or other search engines. Some sourcing and recruiting professionals may be surprised to learn that Boolean logic significantly predates the Internet and even computers – by a couple hundred years!

The word “Boolean” comes from the man who invented Boolean Logic in the 19th century – George Boole. Boolean Logic is the basis of modern computer logic, and George Boole is regarded in hindsight as one of the founders of the field of computer science.

Now that you know Boolean logic was created in the 1800’s – it’s pretty obvious that Boolean logic is not just for searching for people and information on the Internet. Practically any information system from which you need to search and retrieve information from “speaks” Boolean to some extent, whether you realize it or not.

Applicant Tracking Systems

I was first exposed to Boolean search back in 1997 B.G. (Before Google) when my sole source of candidates was a Lotus Notes resume database by the name of CPAS, made by VCG. Although the CPAS product (which no longer exists) was far from a fully featured Applicant Tracking System, thankfully it did support full Boolean logic, with very few limitations. If it didn’t support full Boolean logic, this blog would probably would not exist – and if it did, I wouldn’t be writing it. Thank you CPAS!

The CPAS search interface allowed me to hand-code highly precise and effective Boolean search strings using all three standard Boolean operators: AND, OR, and NOT. While there are some applicant tracking systems on the market that do support full Boolean logic, it is an unfortunate fact that too many ATS’s available today do not support creating searches using full Boolean logic, which significantly handicaps sourcers and recruiters from leveraging their internal corporate candidate databases.

Job Boards

In contrast – all of the major job board resume databases (Monster, Careerbuilder, Hotjobs, Dice, etc.) support full Boolean logic. As I have written about many times before, Monster even supports “extended” Boolean search functionality with the incredibly powerful NEAR operator.

Social Networks

While most social networks are painfully difficult to search with their extremely limited search interfaces, LinkedIn does support creating search strings employing full Boolean logic. In fact, it appears that you can create Boolean search strings of unprecedented length and complexity on LinkedIn. If you haven’t already, please read this post I wrote that compares searching LinkedIn using LinkedIn’s search interface with searching Linkedin using Google and the x-ray technique. I got tired of entering words into LinkedIn’s search bar after cramming 316,638 characters into it. That’s the equivalent of a Boolean search string that contains over 60,000 words and is approximately 120 pages long!

Internet Search

What’s especially ironic about the wide spread perception that Boolean = Internet search is that most Internet search engines don’t even support full Boolean logic. For example, although Google supports Boolean search strings containing AND, OR, and NOT (with the minus sign) functionality, you cannot use the NOT/- operator on an OR statement.

Let’s look at the results when we try and run this search string on Google: Continue reading

Basic Boolean Search Operators and Query Modifiers Explained

 

Basic Boolean Operators Explained

No, those aren’t my hands.

I never cease to be amazed by what you can find on the Internet and what people take pictures of.

Now that I have your attention, this post is going to focus on the basic Boolean search operators and search modifiers symbols and will not go into any detail of the many special Internet-only search commands/operators.

Although a great many people seem to think that Boolean = Internet search, Boolean logic and searching has been around WAY before the Internet. And here’s a quick fact: you don’t have to capitalize Boolean operators on any of the major job boards and many of the major ATS’s.

Go ahead – try it. Nothing will explode and your searches will execute.

And now, back to the Boolean basics…

Boolean Search Operator: AND

The AND operator is inclusionary and thus limits your search.

It should be used for targeting required skills, experience, technologies, or titles you would like to limit your results to. Unless you are searching for common words, with every AND you add to your Boolean query, the fewer results you will typically get.

Example: Java AND Oracle AND SQL AND AJAX

On most Internet search engines and LinkedIn, every space is an “implied AND,” and you don’t have to type it, as every blank space is interpreted as an AND operator.

Example: Java Oracle SQL AJAX

Bonus: You can use the ampersand (&) as the AND operator on Monster.

Boolean Search Operator: OR

The OR operator offers flexible inclusion, and typically broadens your search results.

Many people incorrectly think the Boolean OR operator is an either/or operator, when in fact it is not.

The OR operator is technically interpreted as “at least one is required, more than one or all can be returned.”

Although some search engines, such as Google, do not require you to encapsulate OR statements with parentheses, if you don’t on most databases and LinkedIn – your search will run but execute in a way that you probably did not intent.  As a best practice, I tell people to always use parentheses around OR statements as a matter of good search syntax.

Example: Java AND Oracle AND SQL AND AJAX AND (apache OR weblogic OR websphere)

The returned results must mention at least one of the following: apache, weblogic, websphere. However, if candidates mention 2 or all 3, they also will be returned, and most search engines will rank them as more relevant results because of such.

The best ways to use OR statements is:

  1. To think of all of the alternate ways a particular skill or technology can be expressed, e.g., (CPA OR “C.P.A” OR “Certified Public Accountant”)
  2. To search for a list of desired skills where you would be pleased if a candidate had experience with at least one, e.g., (apache OR linux OR mysql).

Bonus: You can use the pipe symbol (|) for the OR operator on Google, Bing, and Monster.

Boolean Search Operator: NOT

The NOT operator is exclusionary – it excludes specific search terms and so the query will not return any results with that term (or terms) in them.

Example: If you were searching for an I.T. Project Manager, you may want to employ the NOT operator in order to eliminate false positive results – results that mention your search terms but do not in fact match your target hiring profile.  In this case, you could run: “project manager” and not construction – this search will not return any results with “project manager” and the word “construction” contained within them.

On all of the major job board resume databases, some ATS’s and LinkedIn, you can use the NOT operator in conjunction with an OR statement.

Example: .Net AND NOT (Java OR JSP OR J2EE) – that search will not return any results with any mention of Java, JSP, and/or J2EE.

Bonus: NOT has 2 main uses

  1. Excluding words you do not want to retrieve to reduce false positive results (most common usage)
  2. Starting with a very restrictive search with many search terms, you can use the NOT operator to systematically and progressively loosen the search into mutually exclusive result sets (not so common usage, but very effective strategy)

Basic example:

  1. “Project Manager” AND SQL AND Spanish
  2. “Project Manager” AND SQL AND NOT Spanish
  3. “Project Manager” AND NOT SQL AND Spanish
  4. “Project Manager” AND NOT (SQL OR Spanish)

Bonus: You can use the minus sign as the NOT operator on many sites and search engines, including LinkedIn.

Boolean Search Modifier: ASTERISK *

The asterisk can be used on most resume databases and non-Internet search engines as a root word/stem/truncation search. In other words, the search engine will return and highlight any word that begins with the root/stem of the word truncated by the asterisk.

For example: admin* will return: administrator, administration, administer, administered, etc.

The asterisk is a time saver for search engines that recognize it (most major job boards and ATS’s) because it saves you from creating long OR statements and having to think of every way a particular word can be expressed.

LinkedIn does not support the asterisk, so you will have to construct large OR statements to search for all of the various ways someone could mention each term you’re searching for. For example: (configure OR configuring OR configured OR configures)

Boolean Search Modifier: PARENTHESES

As a best practice, use parentheses to encapsulate OR statements for the search engines to execute them properly.

Remember, the OR operator is interpreted as “I would like at least one of these terms.” Think of parentheses as your way of telling the search engine you’re looking for one of THESE: (_______________).

For example: (apache OR weblogic OR websphere)

If you don’t enclose all of your OR statements, your search may run but it will NOT run as intended.

Boolean Search Modifier: QUOTATION MARKS ” “

Quotation marks must be used when searching for exact phrases of more than one word, or else some search engines will split the phrase up into single word components.

For example: “Director of Tax” will only return “Director of Tax.” If you searched for Director of Tax without the quotation marks, on some search engines, it will split up the words Director and Tax and highlight them as relevant matches even when not mentioned as an exact phrase.

Bonus: Google auto-stems many search terms, so if you are looking specifically for the word manager, it will still return managed, management, etc. – even if you don’t want it to. If you put quotation marks on a single word in Google, it will defeat the auto-stemming feature and only return that specific word.

There you have it – Boolean basics!

If there is something you would like to see me post about with regard to Boolean logic and search tactics and strategies – let me know.

Thanks!