dtSearch Search Help


Introduction

To search, enter a search request in the space provided and click the Search button.   A list of matching documents will appear.  To view a document in the list, click on the link.  After you have opened a document, you can use the Next Hit and Prev Hit buttons on the button bar to navigate from hit to hit.  (For PDF files, use the hit navigation buttons in the Adobe Reader toolbar.  Click here for more information.) 

Search Requests Overview

dtSearch supports two types of search requests:

An any words search is any sequence of text, like a sentence or a question.  In an any words search, use quotation marks around phrases, put + in front of any word or phrase that is required, and - in front of a word or phrase to exclude it.  Examples:

banana pear "apple pie"

"apple pie" -salad +"ice cream"

An all words search is like an any words search, except that all of the terms have to be found in a document.

A boolean search request consists of a group of words or phrases linked by connectors such as and and or that indicate the relationship between them. Examples:

apple and pear Both words must be present
apple or pear Either word can be present
apple w/5 pear Apple must occur within 5 words of pear
apple not w/5 pear Apple must not occur within 5 words of pear
apple and not pear Only apple must be present
author contains smith The field author must contain smith

If you use more than one connector, you should use parentheses to indicate precisely what you want to search for. For example, apple and pear or orange juice could mean (apple and pear) or orange, or it could mean apple and (pear or orange).

Search Features

stemming

Finds grammatical variations on endings, like applies, applied, applying in a search for apply

fuzzy searching

Finds words even if they are misspelled.  A search for alphabet with a fuzziness of 1 would also find alphaqet.  With a fuzziness of 3, the same search would find both alphaqet and alpkaqet

phonic searching

Finds words that sound alike, like Smythe in a search for Smith

synonym expansion

Finds word synonyms using a comprehensive English language thesaurus (dtSearch Web can also support custom thesaurus terms)

 

Search terms may include the following special characters:

?

Matches any single character. Example: appl? matches apply or apple.

*

Matches any number of characters. Example: appl* matches application

~

Stemming. Example: apply~ matches apply, applies, applied.

%

Fuzzy search. Example: ba%nana matches banana, bananna.

#

Phonic search. Example: #smith matches smith, smythe.

&

Synonym search. Example: fast& matches quick.

~~

Numeric range. Example: 12~~24 matches 18.

:

Variable term weighting. Example: apple:4 w/5 pear:1

Words and Phrases

Use quotation marks to indicate a phrase.  You can use a phrase anywhere in a search request. Example:

apple w/5 "fruit salad"

If a phrase contains a noise word, dtSearch will skip over the noise word when searching for it. For example, a search for statue of liberty would retrieve any document containing the word statue, any intervening word, and the word liberty.

Punctuation inside of a search word is treated as a space. Thus, can't would be treated as a phrase consisting of two words: can and t. 1843(c)(8)(ii) would become 1843 c 8 ii (four words).

Noise words, such as if and the, are ignored in searches.

Wildcards (* and ?)

A search word can contain the wildcard characters * and ?. A ? in a word matches any single character, and a * matches any number of characters. The wildcard characters can be in any position in a word. For example:

appl* would match apple, application, etc.
*cipl* would match principle, participle, etc.
appl? would match apply and apple but not apples.
ap*ed would match applied, approved, etc.

Use of the * wildcard character near the beginning of a word will slow searches somewhat.

Synonym Searching

Synonym searching finds synonyms of a word in a search request. For example, a search for fast would also find quick. You can enable synonym searching for all words in a request or you can enable synonym searching selectively by adding the & character after certain words in a request. Example: fast& w/5 search.

The effect of a synonym search depends on the type of synonym expansion requested on the search form. dtSearch can expand synonyms using only user-defined synonym sets, using synonyms from dtSearch's built-in thesaurus, or using synonyms and related words (such as antonyms, related categories, etc.) from dtSearch's built-in thesaurus.

Fuzzy Searching

Fuzzy searching will find a word even if it is misspelled. For example, a fuzzy search for apple will find appple. Fuzzy searching can be useful when you are searching text that may contain typographical errors, or for text that has been scanned using optical character recognition (OCR). There are two ways to add fuzziness to searches:

  1. Check the "Fuzzy searching" box to enable fuzziness for all of the words in your search request. You can adjust the level of fuzziness from 1 to 10.
  2. You can also add fuzziness selectively using the % character. The number of % characters you add determines the number of differences dtSearch will ignore when searching for a word. The position of the % characters determines how many letters at the start of the word have to match exactly. Examples:

Phonic Searching

Phonic searching looks for a word that sounds like the word you are searching for and begins with the same letter. For example, a phonic search for Smith will also find Smithe and Smythe.

To ask dtSearch to search for a word phonically, put a # in front of the word in your search request. Examples: #smith, #johnson

You can also check the Phonic searching box in the search form to enable phonic searching for all words in your search request. Phonic searching is somewhat slower than other types of searching and tends to make searches over-inclusive, so it is usually better to use the # symbol to do phonic searches selectively.

Stemming

Stemming extends a search to cover grammatical variations on a word. For example, a search for fish would also find fishing. A search for applied would also find applying, applies, and apply. There are two ways to add stemming to your searches:

    1. Check the Stemming box in the search form to enable stemming for all of the words in your search request. Stemming does not slow searches noticeably and is almost always helpful in making sure you find what you want.
    2. If you want to add stemming selectively, add a ~ at the end of words that you want stemmed in a search. Example: apply~

Variable Term Weighting

When dtSearch sorts search results after a search, by default all words in a request count equally in counting hits. However, you can change this by specifying the relative weights for each term in your search request, like this:

apple:5 and pear:1

This request would retrieve the same documents as apple and pear but, dtSearch would weight apple five times as heavily as pear when sorting the results.

In a natural language search, dtSearch automatically weights terms based on an analysis of their distribution in your documents. If you provide specific term weights in a natural language search, these weights will override the weights dtSearch would otherwise assign.

Field Searching

When you index a database or other file containing fields, dtSearch saves the field information so that you can perform searches limited to a particular field. For example, suppose that you indexed an Access database with a Name field and a Description field. You could search for apple in the Name field like this:

name contains apple

Field searches can be combined using and, or, and not, like this:

(City contains (portland or Seattle)) and (Address contains (Washington))

The parenthesis are necessary to ensure that dtSearch interprets the search request correctly.

Some file formats such as XML support nesting of fields. Example:

<record>
     <name>John Smith</name>
     <address>
           <street>123 Oak Street</street>
           <city>Middleton</city>
           ...

In dtSearch, a search of a field includes any fields that are nested inside of the field, so the XML file above would be retrieved in a search for any of the following:

record contains oak
address contains oak
street contains oak

To specify a specific subfield of a field, use / to separate the field names, like this:

record/address contains oak
address/street contains oak
record/address/street contains oak

Put a / at the front of the field name to specify that it cannot be a sub-field of another field:

/record/name contains Smith
/name contains Smith

The second search request above would not match the XML example because, while it contains a "name" field, the name field is a sub-field of the record-field. A search for /name specifies a "name" field at the top of the field hierarchy.

Finally, you can use // to specify any number of unspecified intervening fields, like this:

/record//city contains Middleton

AND Connector

Use the AND connector in a search request to connect two expressions, both of which must be found in any document retrieved. For example:

apple pie and poached pear would retrieve any document that contained both phrases.

(apple or banana) and (pear w/5 grape) would retrieve any document that (1) contained either apple OR banana, AND (2) contained pear within 5 words of grape.

OR Connector

Use the OR connector in a search request to connect two expressions, at least one of which must be found in any document retrieved. For example, apple pie or poached pear would retrieve any document that contained apple pie, poached pear, or both.

W/N Connector

Use the W/N connector in a search request to specify that one word or phrase must occur within N words of the other. For example, apple w/5 pear would retrieve any document that contained apple within 5 words of pear. The following are examples of search requests using W/N:

(apple or pear) w/5 banana
(apple w/5 banana) w/10 pear
(apple and banana) w/10 pear

Some types of complex expressions using the W/N connector will produce ambiguous results and should not be used. The following are examples of ambiguous search requests:

(apple and banana) w/10 (pear and grape)
(apple w/10 banana) w/10 (pear and grape)

In general, at least one of the two expressions connected by W/N must be a single word or phrase or a group of words and phrases connected by OR. Example:

(apple and banana) w/10 (pear or grape)
(apple and banana) w/10 orange tree

dtSearch uses two built in search words to mark the beginning and end of a file: xfirstword and xlastword. The terms are useful if you want to limit a search to the beginning or end of a file. For example, apple w/10 xlastword would search for apple within 10 words of the end of a document.

NOT and NOT W/N

Use NOT in front of any search expression to reverse its meaning. This allows you to exclude documents from a search. Example:

apple sauce and not pear

NOT standing alone can be the start of a search request. For example, not pear would retrieve all documents that did not contain pear.

If NOT is not the first connector in a request, you need to use either AND or OR with NOT:

apple or not pear
not (apple w/5 pear)

The NOT W/ ("not within") operator allows you to search for a word or phrase not in association with another word or phrase. Example:

apple not w/20 pear

Unlike the W/ operator, NOT W/ is not symmetrical. That is, apple not w/20 pear is not the same as pear not w/20 apple. In the apple not w/20 pear request, dtSearch searches for apple and excludes cases where apple is too close to pear. In the pear not w/20 apple request, dtSearch searches for pear and excludes cases where pear is too close to apple.

Numeric Range Searching

A numeric range search is a search for any numbers that fall within a range. To add a numeric range component to a search request, enter the upper and lower bounds of the search separated by ~~ like this:

apple w/5 12~~17

This request would find any document containing apple within 5 words of a number between 12 and 17.

Numeric range searches only work with positive integers. A numeric range search includes the upper and lower bounds (so 12 and 17 would be retrieved in the above example).

For purposes of numeric range searching, decimal points and commas are treated as spaces and minus signs are ignored. For example, -123,456.78 would be interpreted as: 123 456 78 (three numbers). Using alphabet customization, the interpretation of punctuation characters can be changed. For example, if you change the comma and period from space to ignore, then 123,456.78 would be interpreted as 12345678.


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