Boolean Searching in SLM Digital Collections

In a previous post, we learned about how to start a search in the State Library of Massachusetts Digital Collections (SLM Digital Collections). Today we are going to take a closer look at a search refining technique called a Boolean search, which you can use to construct searches that will more precisely yield the results (and items) you are looking for.

Although some of the overall functionality and appearance of our digital repository changed significantly during the upgrade to the newest version of the platform for our digital collections, the ability to do a Boolean search remained the same. For patrons who interacted with the version of DSpace we used for our digital collections prior to the upgrade, the steps for how to do a Boolean search will seem very familiar. And if this is your first time visiting the SLM Digital Collections or you want a refresher on Boolean searching, the instructions in this post can help you find out how to do a Boolean search.

First, we will review what a Boolean search is—it is a kind of search commonly used on websites and search engines where you can limit, define, or broaden your search using operators and symbols.

The operators commonly used and what we use for Boolean searches in SLM Digital Collections are AND, OR and NOT. It is important to note that the plus sign (+) commonly used as a substitute for AND is not enabled as a Boolean operator for searching our digital collections. Neither is the minus sign (-), commonly used as a substitute for NOT, enabled in the search functions.

To use Boolean operators either use in all caps or all lowercase between each keyword. Each operator functions in a unique way:

• AND returns results with words appearing together in documents (example: boats AND harbors)
• OR returns results for documents containing either word (example: boats OR harbors)
• NOT returns results for documents containing one word and excluding the other word (example: boats NOT harbors)

Any query of 2 or more words essentially operates as the “AND” in a Boolean search and will yield results with both or all the words from the search in it. We will go through an example of how to apply a Boolean operator in the search box. So, if we typed into the search box boats harbor it yields the same number of results as if we had entered boats AND harbor. The query doesn’t have to be a phrase in this case but can be words that appear together in the documents we want to see. We can use more than 2 words at a time like in the query boats AND harbor AND fish.

Of course, we can also use the Boolean operator AND for pairing together specific phrases to find a specific set of documents. In this case we are interested in finding back issues of DMF News because we remember there was at least one issue that mentioned bluefin tuna fisheries, the Boston harbor and party boats all in the same issue. Rather than navigating through the maze of the communities and collections associated with Department of Marine Fisheries in SLM Digital Collections we can create a Boolean search for this that will find the DMF News issue(s) we are looking for.

First, we need to navigate to the search results page and select the community Division of Marine Fisheries to be entered inside the box next to the search box. The second step is coming up with a list of phrases to use-- bluefin tuna fishery, Boston Harbor, charter and party boats, and DMF News. Now we need to format the phrases properly to construct the search query. When using specific phrases in a DSpace search, Boolean or otherwise, it is important to add quotation marks around the phrase. In this case to construct the search query we need to enter “bluefin tuna fisheries” AND “Boston Harbor” AND “charter and party boats” AND “DMF News” in the search box and press enter, which should return only 10 results for back issues of DMF News covering these topics.

However, we’re seeing some results that aren’t issues of DMF News. It looks like the majority of them are DMF annual reports. This simply means we need to be a little more specific with the phrase “DMF News” in the query string.

To do this we can search with the title field (dc.title) by rewriting this portion of the string as AND dc.title:”DMF News.” And the 10 issues of DMF News are now the only items appearing in the search results.

However, we decided that we only want the issues mentioning the Boston harbor and party boats. If we removed the phrase “bluefin tuna fisheries” from the beginning of our query and moved it to the end using the NOT operator like this “Boston Harbor” AND “charter and party boats” AND dc.title:”DMF News” NOT “bluefin tuna fisheries,” we would get results that excludes the phrase bluefin tuna fisheries but does include results of Boston Harbor and charter and party boats appearing specifically in 3 issues of DMF News.

Now that we have gone over how to do Boolean searching on the SLM Digital Collections website, you have the know-how to do your own Boolean searches!

If you are feeling stuck at any point using Boolean operators in a search while using SLM Digital Collections, you can reach out to our reference department for assistance by email or by calling 617-927-2590. Or if you are visiting our reading room, come up to the reference desk and someone can help you.

Emily Crawford

Technical Services Librarian