Support : Dialog Search Aids : Successful Searching : SELECT : Order of Processing

SELECT (continued)

Order of Processing

Dialog first processes any proximity operators that it finds in a SELECT statement. The next operator to be processed is NOT, followed by AND, and finally OR. To vary this order, place parentheses around the group of terms and operators that must be processed first. Parentheses are most often used to specify that an OR combination be processed before an AND combination. You may use more than one level of parentheses in a SELECT statement; the innermost group is processed first.

(T)	Used for chemical name searching in selected files; used to retrieve one part of a chemical name with another part.
(W)	Requests that terms be adjacent to each other and in the order specified. Can also be used to retrieve identical terms.
(N)	Requests that terms be adjacent but in any order. Can also be used to retrieve identical terms.
(S)	Requests that terms be in the same subfield unit as defined by the database. In full-text files, requests that terms be in the same paragraph.
(L)	Requests that terms be in the same descriptor unit as defined by the database (i.e., heading-subheading entries, such as SOLAR-ENERGY).
(F)	Requests that terms be in the same field, as defined by the database.

The following example uses parentheses to search for records on hypercube theorems or hypercube algorithms. The second example searches for records on design aspects of either multidimensional graphs or multidimensional cubes.

• To use parentheses to change the order of processing:

?select (theorem or algorithm) and hypercube?
           20238  THEOREM
           44275  ALGORITHM
            1295  HYPERCUBE?
      S3     717  (THEOREM OR ALGORITHM) AND HYPERCUBE?

• To use more than one level of parentheses:

?s (multi(w)dimensional or multidimensional) and (graph? or 
cube?) and design?
           15626  MULTI
          135925  DIMENSIONAL
             862  MULTI(W)DIMENSIONAL
            7422  MULTIDIMENSIONAL
           43030  GRAPH?
            1833  CUBE?
          133391  DESIGN?
      S4      42  (MULTI(W)DIMENSIONAL OR MULTIDIMENSIONAL)
                  AND (GRAPH? OR CUBE?) AND DESIGN?

(File 34: SciSearch^®: a Cited Reference Science Database)

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