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Operators and Modifiers

Operators

An operator represents logic to be applied to a search element. This logic defines the qualifications a document must meet to be retrieved. Operators are used to refine your search or to influence the results in other ways. You can refine your search by limiting the search scope in a number of ways. Operators are available for limiting a query to a sentence or paragraph, and you can search words based on proximity. The following operator types are available:

Ordinarily, you use operators in explicit searches. They are used in the following manner:

"<operator>search_string"

Evidence operators

Evidence operators can be used to specify either a basic word search or an intelligent word search. A basic word search finds documents that contain only the word or words specified in the query. An intelligent word search expands the query terms to create an expanded word list so that the search returns documents that contain variations of the query terms.

Documents retrieved using evidence operators are not ranked by relevance unless you use the MANY modifier.

Verity Evidence Operators 
Operator Description
STEM Expands the search to include the word you enter and its variations. The STEM operator is automatically implied in any SIMPLE query. For example, the EXPLICIT query expression <STEM>believe yields matches such as, "believe," "believing," "believer".'
WILDCARD Matches wildcard characters included in search strings. Certain characters automatically indicate a wildcard specification, such as * and?. For example, the query expression spam* yields matches such as, "spam," "spammer," "spamming."
WORD Performs a basic word search, selecting documents that include one or more instances of the specific word you enter. The WORD operator is automatically implied in any SIMPLE query.

Proximity operators

Proximity operators specify the relative location of specific words in the document. Specified words must be in the same phrase, paragraph, or sentence for a document to be retrieved. In the case of NEAR and NEAR/N operators, retrieved documents are ranked by relevance based on the proximity of the specified words. Proximity operators can be nested; phrases or words can appear within SENTENCE or PARAGRAPH operators, and SENTENCE operators can appear within PARAGRAPH operators.

The following table describes each operator.

Verity Proximity Operators 
Operator Description
NEAR Selects documents containing specified search terms. The closer the search terms are to one another within a document, the higher the document's score. The document with the smallest possible region containing all search terms always receives the highest score. Documents whose search terms are not within 1000 words of each other are not selected.
NEAR/N Selects documents containing two or more search terms within N number of words of each other, where N is an integer between 1 and 1024 where NEAR/1 searches for two words that are next to each other. The closer the search terms are within a document, the higher the document's score. You can specify multiple search terms using multiple instances of NEAR/N as long as the value of N is the same: commute <NEAR/10> bicycle <NEAR/10> train <NEAR/10>
PARAGRAPH Selects documents that include all of the words you specify within the same paragraph. To search for three or more words or phrases, you must use the PARAGRAPH operator between each word or phrase.
PHRASE Selects documents that include a phrase you specify. A phrase is a grouping of two or more words that occur in a specific order. Examples of phrases: mission oak "mission oak" mission <PHRASE> oak <PARAGRAPH> (mission, oak)
SENTENCE Selects documents that include all of the words you specify within the same sentence. Examples: jazz <SENTENCE> musician <SENTENCE> (jazz, musician)

Relational operators

Relational operators search document fields that have been defined in the collection. Documents containing specified field values are returned. Documents retrieved using relational operators are not ranked by relevance, and you cannot use the MANY modifier with relational operators.

The following operators are used for numeric and date comparisons.

Verity Numerical and Date Relational Operators 
Operator Description
= Equals
> Greater than
>= Greater than or equal to
< Less than
<= Less than or equal to

Text comparison operators match words and parts of words. The following operators are used for text comparisons.

VerityText Comparison Operators 
Operator Description
CONTAINS Selects documents by matching the word or phrase you specify with the values stored in a specific document field. Documents are selected only if the search elements specified appear in the same sequential and contiguous order in the field value. For example, specifying "god" will match "God in heaven," "a god among men," or "good god" but not "godliness," or "gods."
MATCHES Selects documents by matching the query string with values stored in a specific document field. Documents are selected only if the search elements specified match the field value exactly. If a partial match is found, a document is not selected. For example, specifying "god" will match a document field containing only "god" and will not match "gods," "godliness," or "a god among men."
STARTS Selects documents by matching the character string you specify with the starting characters of the values stored in a specific document field.
ENDS Selects documents by matching the character string you specify with the ending characters of the values stored in a specific document field.
SUBSTRING Selects documents by matching the query string you specify with any portion of the strings in a specific document field. For example, specifying "god" will match "godliness," "a god among men," "godforsaken," etc.

Concept operators

Concept operators combine the meaning of search elements to identify a concept in a document. Documents retrieved using concept operators are ranked by relevance. The following table describes each concept operator.

Verity Concept Operators 
Operator Description
AND Selects documents that contain all of the search elements you specify.
OR Selects documents that show evidence of at least one of the search elements you specify.
ACCRUE Selects documents that include at least one of the search elements you specify. Documents are ranked based on the number of search elements found.

Score operators

Score operators govern how the search engine calculates scores for retrieved documents. The maximum score a returned search element can have is 1.000. The score percentage display can optionally be set to as many as four decimal places.

When a score operator is used, the search engine first calculates a separate score for each search element found in a document, and then performs a mathematical operation on the individual element scores to arrive at the final score for each document.

Note that the document's score is available as a result column. The SCORE result column can be referenced to trap the relevancy score of any document retrieved.

The following table lists the score operators.

Verity Score Operators 
Operator Description
YESNO Forces the score of an element to 1 if the element's score is non-zero: <YESNO>mainframe If the retrieval result of the search on "mainframe" is 0.75, the YESNO operator forces the result to 1. You can use YESNO to avoid relevance ranking.
PRODUCT Multiplies the scores for documents matching a query. To arrive at a document's score, the search engine calculates a score for each search element and multiplies these scores together: <PRODUCT>(computers, laptops) The resulting score for each document is multiplied together.
SUM Adds together the scores for documents matching a query, up to a maximum value of 1: <SUM>(computers, laptops) The resulting scores are added together.
COMPLEMENT Calculates scores for documents matching a query by taking the complement (subtracting from 1) of the scores for the query's search elements. The new score is 1 minus the search element's original score. <COMPLEMENT>computers If the search element's original score is.785, the COMPLEMENT operator recalculates the score as.215.

Modifiers

Modifiers can be used with operators to further refine query expressions. You can specify case sensitivity in a query, or force the output to be ranked by relevancy. Modifiers include:

Search modifiers

Modifiers are combined with operators to change the standard behavior of an operator in some way. For example, you can use the CASE modifier with an operator to specify that you want to match the case of the search word.

Modifiers are as follows.

Verity Search Modifiers 
Modifier Description
CASE Specifies a case-sensitive search: <CASE>J[JAVA, java] Searches for "JAVA" and "Java." If a search contains a mixed-case string, the search request will be case-sensitive.
MANY Counts the density of words, stemmed variations, or phrases in a document and produces a relevance-ranked score for retrieved documents. Can be used with the following operators: WORD WILDCARD STEM PHRASE SENTENCE PARAGRAPH <PARAGRAPH><MANY>javascript <AND> vbscript The MANY modifier cannot be used with the following: AND OR ACCRUE Relational operators
NOT Used to exclude documents that contain the specified word or phrase. Used only with the AND and OR operators. Java <AND> programming <NOT> coffee
ORDER Used to specify that the search elements must occur on the same order in which they were specified in the query. Can be used with the following operators: PARAGRAPH SENTENCE NEAR/N Place the ORDER modifier before any operator: <ORDER><PARAGRAPH>("server", "Java")