Appendix 4. Selecting Keywords for Searches

Type a keyword into the blank provided on the search form and then click on the "Search" button.

Keywords are case-insensitive (upper-case and lower case letters are all treated the same during the search). You may include multiple keywords following the guidelines below:

Boolean Expressions

"Boolean Expression" is a nerd term for what you type when you wish to specify two or more keywords. When you use two or more keywords, you must separate them with "boolean connectors". A boolean connector is a word or symbol which denotes the way in which the keywords will be used in the search process.

  1. Searches may use AND, OR, NOT boolean connectors (a space between keywords is treated as AND).
  2. Multiple ANDs, ORs and NOTs can be given.
  3. Upper and lower case are ignored (case-insensitive).
  4. Keywords may be truncated with an '*' as the last character of the root-word.
Examples: 
SUPREME COURT     =  both supreme and court
SUPREME AND COURT =  both supreme and court
LAW OR LEGAL      =  either law or legal
CONSTIT*          =  any word beginning with 'constit'
COURT NOT SUPREME =  all entries with 'court' but excluding any with 'supreme'
You can give boolean expressions with parenthesized sub-expressions as in: 
SUPREME AND (COURT OR BURRITO)
which will match article names that contain 'supreme' and 'court' or articles that have names that contain 'supreme' and 'burrito'. When in doubt about order of evaluation, parenthesize the expression.

Here's a technical description of the Boolean connectors and their use in queries for walker: 

A QUERY consists an Expression, optionally	Query: expr {expr}
followed by another Expression; "AND" is 
assumed between multiple expressions.

Each EXPRESSION contains a Term, optionally	Expr: term {OR term}
followed by "OR" and another Term.

A TERM is a Factor, optionally followed by	Term: factor {and|not factor}
"AND" or "NOT" and another Factor.

A FACTOR can be a Token, or another Query.	Factor: (query) | token

A TOKEN is a keyword.				Token:  keyword

A KEYWORD is a string of alphabetic		Keyword: a-z{a-z}[*]
characters of any length.  An asterisk
indicates that any characters following
those specified should be accepted.