![]() ![]() Think about how many words might start with a root such as car before using truncation. So, as with the not operator you have to be careful when using this operator or you may get a lot of irrelevant records. For example,Īsks the computer to search for both car and cars, or any word beginning with car such as carriage or carburettor. ![]() It is very useful to take into account plural and singular forms of a noun. Truncation allows you to search for all the variants of a word without having to specify them all in your search string. sometimes next is used rather then near - you should check the databases' help pages to find out if and how proximity can be used. ![]() The syntax used for truncation varies amongst databases e.g. Therefore one would use the search string: The near operator requires that a record has terms close together in the text, making it more likely that there is a meaningful link between the terms in the record. May return irrelevant records because red is a very general adjective and could describe many other things in a record. If, for example, you are interested in red cars, a search string such as Proximity searching allows you to specify that records found by your search contain one search term near another. The power of Boolean searching can be extended further by proximity, truncation and wild card operators. ![]() 'cars or automobiles' Proximity, Truncation and Wild Cards For example, cars are also known as automobiles and so to catch as many relevant records in your search as possible, you would use: To search for records that return one or more of your search terms, link them together with the or operator. different spellings (UK versus US spelling, for example).different word endings (singular and plural forms, for example).If your search returns few or no records, you might have more success if you can think of alternative search terms. If you were interested in cars of any colour as long as they are not blue, you would use the following search string: With many databases you will need to use and not rather than not, check the help pages of the database if you are not sure. Be careful when using this, you may miss records that contain useful information because you have excluded too many records. If you do not wish to see records containing a certain term, you can exclude these by using the not operator. To avoid having to sift through records on blue cars, green cars and so on, you would use the following search string: For example, let's say you were interested in only red cars. To make sure that all the records your search finds contain all the search terms, link them with the and operator. If your search returns too many records, you can narrow your search by adding more search terms. By the use of a few simple linking words, called operators, you can make your searches much more precise. To do this with databases you need to know about the Boolean system. The database can do a lot of work for you if you take the trouble to add a little sophistication to your search strings. By putting a little effort into constructing search strings (what you type into the search box) you can save a lot of time. It takes a long time to look at hundreds of records. Most searches will return too many or too few records. Boolean Searching What is Boolean Searching? Not all the techniques covered here will be supported by all databases - you are advised to look at the help pages as you learn to use a new database since that will save you a lot of time and frustration. The techniques explained in this page will help you become the fast, effective searcher you really need to be as a distance learning student relying on online information sources. ![]()
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