Avanti MicroLCS provides a simple yet very powerful OPAC search interface that can do simple keyword searching on a single index all the way up to full boolean searching across multiple fields and nested search capability.

The Search Interface

MicroLCS provides one single-line search interface for both simple and complex searches. It consists of a drop-down select field to choose an index to search on, a single generously sized search input line to enter search terms and a "Find" button to execute the search. Unlike most other OPAC software, MicroLCS does not have a basic - advanced user dichotomy. "Basic" and "advanced" are relative concepts that exist on a continuum and vary from user to user. So MicroLCS reflects this philosophy by providing all search features in one simple interface. The power lies in an easy to learn search syntax that provides unrestricted boolean, cross-index, and nested searching. This is a much more elegant and flexible design than the often clumsy, confusing and limiting array of input fields, AND/OR/NOT selectors and other bells and whistles found on the advanced search screens of most OPACs.

Keyword Searching

Basic keyword searching is very simple. Just select the index to search on, enter one or more keywords separated by spaces and click the Find button. Multiple search words are automatically ANDed together so the more search words in a search the narrower and more refined the results will be. So for example selecting the Subject index, entering

dogs

dogs cats

in the search line returns all titles that have both keywords "dogs" and "cats" in the subject field. Note the implied AND in this example.

All searches in MicroLCS are case insensitive. So entering

dogs cats

returns the same results as

Dogs Cats

Boolean Searching

As pointed out earlier basic keyword searching is a form of boolean searching . Anytime two or more keywords are entered without boolean operators there is an implied AND between them. MicroLCS provides full and unrestricted boolean keyword searching using a simple search syntax. Boolean searches are composed of keywords and operators on the keywords. MicroLCS supports the three basic Boolean operators: AND, OR and NOT. These are represented by the following symbols:

+     AND

^     OR

!     NOT

NOTE: keywords and operators are ALWAYS separated with spaces.

So for example, a subject search on dogs AND cats is typed as

dogs + cats

in the search line. This returns all titles with both the words "dogs" and "cats" appearing in the subject field. Likewise, dogs OR cats is typed as

dogs ^ cats

and returns all titles with either the word "dogs" in the subject field or "cats" in the subject field or both "dogs" and "cats."

The NOT operator (!) is used to exclude or subtract a keyword or search expression from a search. For example,

mammals ! cats

will return all titles with "mammals" but not "cats" in the subject field.

MicroLCS can support many keywords and boolean operators in a search. The following are all valid searches:

dogs + cats + rabbits + horses

dogs ^ cats ^ rabbits ! horses

horse ^ equine ! morgan

Cross-index Searching

MicroLCS is also able to search across any and all indexed fields in a search. The examples above were Subject searches. We could also specify another indexed field in a search. This is done by prefixing the new search field with a "$". For example, the subject search

horse ^ equine ! morgan $author henry

Returns all titles that have a subject containing the words "horse" or "equine" but not "morgan" that are by authors named "henry." Only indexed fields can be used for cross-indexing. Once a new indexed field is specified in the search all subsequent keywords in the search will be processed against the new indexed field until a different indexed field is specified.

Nested Searches

We can already do quite a few useful things with the basic keyword searching, boolean searching and cross-indexing capabilities available to us in MicroLCS. These are made much more powerful with nested searching. All searches in MicroLCS are evaluated from left to right. With nested searching we can group keywords and boolean expressions to set precedence. Nesting searches is done by enclosing parts of the search in curly braces { }. So in the example

mammals ! { cats ^ dogs }

the boolean expression {cats ^ dogs} is evaluated first and the results of that expression is NOTed with (or subtracted from) "mammals." Essentially this search returns all records containing the word "mammals" but not "cats" or "dogs." Note that the curly braces are separated by spaces from operators and keywords. A nested search can be thought of as a search within a search.

This example,

mammals + { cats ^ dogs }

returns titles containing the word "mammals" together with "cats" or "dogs." Much different than

mammals + cats ^ dogs

Which returns titles containing the words "mammals" and "cats" and all titles about dogs.

Multiple levels of nesting are also valid. This example,

mammals + { cats ^ dogs ^ { horses + morgan } }

returns all titles about mammals that are cats or dogs or morgan horses. In this example we're already treading ground that is beyond the capability of many OPAC search interfaces, since nested searching is not a common feature. And these are but simple examples of what is capable with the MicroLCS search interface.

MicroLCS has no practical limit to the number of keywords in a search or the complexity of boolean searches. It will evaluate many levels of nesting and complexity within each level. If a boolean search can be correctly expressed, MicroLCS should be able to evaluate it and return the results. Furthermore, because the search expression is not erased after hitting the Find button searches can be "fine-tuned" as you go. With full boolean keyword search capabilities, cross-index searching, and nested searching brought together in a simple and easy to learn interface, MicroLCS provides a keyword search tool with a power and flexibility that rivals or exceeds the capability of most any other OPAC.

Less is more.