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Using a sophisticated, yet easy-to-use query language, it is possible to construct accurate search queries on archived information. The constituents of query language are discussed further below.

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Terms

 


Fields

 

Boolean Operators

 

Boolean operators allow terms to be combined through logic operators. Архива supports AND, "+", OR, NOT and "-" as boolean operators (Note: boolean operators must be ALL CAPS).

 

The OR operator is the default conjunction operator. This means that if there is no Boolean operator between two terms, the OR operator is used. The OR operator links two terms and finds a matching document if either of the terms exist in a document. This is equivalent to a union using sets. The symbol || can be used in place of the word OR.

 

To search for documents that contain either "apple pear" or just "apple" use the query:

 


 

AND


The AND operator matches documents where both terms exist anywhere in the text of a single document. This is equivalent to an intersection using sets. The symbol && can be used in place of the word AND.

To search for documents that contain "jakarta apache" and "Apache Lucene" use the query:
 

"apple pear" AND "orange grapefruit"

+

 

The "+" or required operator requires that the term after the "+" symbol exist somewhere in a the field of a single document.

To search for documents that must contain "apple" and may contain "pear" use the query:

 

+apple pear

NOT


The NOT operator excludes documents that contain the term after NOT. This is equivalent to a difference using sets. The symbol ! can be used in place of the word NOT.

To search for documents that contain "apple pear" but not "orange grapefruit" use the query:
 

"apple pear" NOT "orange grapefruit"

 

Note: The NOT operator cannot be used with just one term. For example, the following search will return no results:
NOT "apple pear"


The "-" or prohibit operator excludes documents that contain the term after the "-" symbol. To search for documents that contain "apple pear" but not "orange grape fruit" use the query:

 

"apple pear" -"orange grapefruit"


Grouping

 

Field Grouping

 

 

 

Wildcard Searches

 

Архива support single and multiple character wildcard searches within single terms (not within phrase queries).

 

To perform a single character wildcard search use the "?" symbol.

 

To perform a multiple character wildcard search use the "*" symbol.

 

The single character wildcard search looks for terms that match that with the single character replaced. For example, to search for "text" or "test" you can use the search:

 

 

Multiple character wildcard searches looks for 0 or more characters. For example, to search for test, tests or tester, you can use the search:

 

 

You can also use the wildcard searches in the middle of a term.

 

 

 

Fuzzy Searches


Lucene supports fuzzy searches based on the Levenshtein Distance, or Edit Distance algorithm. To do a fuzzy search use the tilde, "~", symbol at the end of a Single word Term. For example to search for a term similar in spelling to "roam" use the fuzzy search:

 

 

This search will find terms like foam and roams.


An additional (optional) parameter can be used to specify the required similarity. The value is between 0 and 1, with a value closer to 1 only terms with a higher similarity will be matched. For example:

roam~0.8

 

 

Proximity Searches

 

Архива supports finding words are a within a specific distance away. To do a proximity search use the tilde, "~", symbol at the end of a Phrase. For example to search for a "apple" and "pear" within 10 words of each other in a document use the search:

 

 

 

Range Searches

 

Range Queries allow one to match documents whose field(s) values are between the lower and upper bound specified by the Range Query. Range Queries can be inclusive or exclusive of the upper and lower bounds. Sorting is done lexicographically.

 

 

This will find documents whose sent date fields have values between 20020101 and 20030101, inclusive. Note that Range Queries are not reserved for date fields. It is possible to use range queries with non-date fields:
 

 

This will find all documents whose titles are between Aida and Carmen, but not including Aida and Carmen. Inclusive range queries are denoted by square brackets. Exclusive range queries are denoted by curly brackets.

 

Boosting a Term

 

Архива provides the relevance level of matching documents based on the terms found. To boost a term use the caret, "^", symbol with a boost factor (a number) at the end of the term you are searching. The higher the boost factor, the more relevant the term will be. Boosting allows one to control the relevance of a document by boosting its term. For example, assuming one is searching for:

 

 

and one wants the term "apple" to be more relevant. Boost it using the ^ symbol along with the boost factor next to the term. Type:

 

 

This will make documents with the term apple appear more relevant. You can also boost Phrase Terms as in the example:

 

 

By default, the boost factor is 1. Although the boost factor must be positive, it can be less than 1 (e.g. 0.2).

 

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