How to Perform a Search

Selecting the language

The most important prerequisite when performing a search is to choose the appropriate language, in which you would like to search. Select the langauge in the header of the page. If you are performing a search for a German document, switch to German (DE). Correspondingly, switch to English (EN) or French (FR) when searching documents in these languages.

 

Basics

A query is broken up into terms and operators. There are two types of terms: single terms and phrases. A single term is a single word such as test or hello. A phrase is a group of words surrounded by quotation marks such as "nano technology". Phrases are searched as given. Multiple terms can be combined together with Boolean operators to form a more complex query (see below). For example, you may search for one or several single terms:

nano scale technology

This query will find all documents that contain all of the above single terms. Note, this is actually an implicit AND boolean operation as described below.

Enter the search terms or phrases into the search field in the header of the page and submit the search query by pressing Enter or clicking on the Search button.

 

Search results

After the search has been executed, the results are presented in the search results page. This page comprises two columns. The right-hand column contains the search results that are ordered according to their relevance. The (smaller) left-hand column contains the search query as well as a set of search filters that may be used to narrow the given results further. Example filters in the following screenshot are asset type, category and (last) modification date.

 

The documents in the result list are ordered according to their relevancy. The computation of the rank involves the number of hits as well as the document part, in which the hit is found. For example, hits have a higher weight if they occur in the title of a document than hits that occur in the actual content. Furthermore, the ranking can be influenced using boosts on fields (see below).

Boolean operators

Boolean operators allow terms to be combined through logic operators. The search supports AND, OR, and NOT as Boolean operators. The operators are English keywords interpreted by the search engine and must be written in upper case letters.

The AND operator is the default operator. This means that if there is no Boolean operator between two terms, the AND operator will be used. Examples:

nano scale technology

This search will find all documents that contain all of the above terms. The following search expression is equivalent:

nano AND scale AND technology

The second Boolean operator is OR. The OR operator links two terms and finds a matching document if either of the terms exist in a document. To search for documents that contain either nano or scale or technology, use the query:

nano OR scale OR technology

The third Boolean operation may be used to exclude documents with a given terms or phrase from the search result. Example:

nano scale NOT technology

This search will find all documents that contain the terms nano and scale but not technology.

Note: using AND and NOT operators narrows the search result list whereas using OR operators broadens the number of search results.

Grouping

The search engine supports using parentheses to group clauses to form sub queries. This can be very useful if you want to control the Boolean logic (AND, OR, NOT) for a query. To search for either nano or scale and technology use the query

(nano OR scale) AND technology

Note: omitting the paranthesis or putting them differently in the query example above will yield another result.

Wildcard search

The search engine supports single and multiple character wildcard searches within single terms (but 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 term with a single character replaced. For example, to search for text or test you can use the search

te?t

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

test*

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

te*t

Note: you cannot use a * or ? symbol as the first character of a search.

Fuzzy search

The search engine supports fuzzy searches. To perform a fuzzy search use the tilde ~ symbol at the end of a Single Term. For example to search for a term similar in spelling to roam use the fuzzy search

roam~

This search will find terms like foam and roams. An additional (optional) parameter can 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

The default parameter is 0.5.

Proximity search

The search engine supports finding words that are a within a specific distance away. To do a proximity search use the tilde (~) symbol at the end of a Phrase followed by a number that is greater than 1. For example to search for nano and scale within 10 words of each other in a document use the search

"nano scale"~10

Search in particular fields

The search engine supports fielded data. A field has a particular semantics and consists of a name and a value. The value is represented in a specific data type, e.g., character string. Many fields are language specific. Thus, you need to add the language identifier to the name of the language-specific fields. Use de_DE for German, en_US for English and fr_FR for French in order to specify the query term for the particular language. The two most important fields are title and content, which are both language-specific. When performing a search without specifying a particular field, the query is executed on a predefined set of fields.

You can search any field by typing the field name followed by a colon : and then the term you are looking for. As an example, if you specify a query for the fields title and content and you want to find the document entitled "The Right Way", which contains the text "don't go this way", you can enter

title_en_US:"Nanotechnology Primer" AND content_en_US:scale

Note: if you specify mutliple terms in a search query, the field name only applies to the immediately following term. Example:

title_en_US:Nanotechnology Primer

This query will only find Nanotechnology in the title field. The term Primer is searched on a predefined set of fields.

The following table provides a selection of fields, which may be of interest for end users. Please note that fields containing a trailing character string <lang-id> are language-specific. In this case, <lang-id> must be substituted with a particular language ID.

Name Data Type Description
articleId String The ID of the web content article (upper case)
assetCategroyTitle_<lang-id> String The name of the asset category
assetTagNames String Nam of the asset tags
content_<lang-id> String The content of the document
createDate String The creation date of the document, ISO Format YYYYMMDDHHSS
displayDate String The (start) display date of the document, ISO Format YYYYMMDDHHSS
expirationDate String The expiration date of the document, ISO Format YYYYMMDDHHSS
firstName String First name of a person
lastName String Last name of a person
publishDate String The publishing date of the document, ISO Format YYYYMMDDHHSS
title_<lang-id> String The title of the document

Grouping within field searches

The search engine supports using parentheses to group multiple clauses to a single field. For example, to search for a title that contains both the word Nanotechnology and the phrase "nano scale" use the query

title_en_US:(Nanotechnology AND "nano scale")

Boosting a term

The search engine 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. This is especially useful if you are doing a OR search, which yields numourous results. Boosting allows you to control the relevance of a document by boosting its term. For example, if you are searching for

nano OR scale

and you want the term nano to be more relevant boost it using the ^ symbol along with the boost factor next to the term. You would type

nano^4 OR scale

This will make documents with the term nano appear more relevant. You can also boost Phrases as in the example

"Nanotechnology primer"^4 "nano scale"

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

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. Inclusive range queries are denoted by square brackets. Exclusive range queries are denoted by curly brackets. Sorting is done lexicographically.

createDate:[20020101 TO 20030101]

This will find documents whose createDate fields have values between 20020101 and 20030101, inclusive. Note that Range Queries are not reserved for date fields. You could also use range queries with non-date fields

title_en_US:{Aluminium TO Iron}

This will find all documents whose titles are between Aluminium and Iron, but not including Aluminium and Iron.

Escaping special characters

The search engine supports escaping special characters that are part of the query syntax. The current list of special characters is

+ - && || ! ( ) { } [ ] ^ " ~ * ? : \

If you search one of the above characters, you need to escape the character, which is done by using the \ before the character. For example, to search for (1+1):2 use the query

\(1\+1\)\:2

Further information
This tutorial has partially been derived from the Lucene query parser documentation.