Alternative Search Suggestions and Automatic Search Expansion

Introduction

Alternative search suggestions

If too few hits have been found for the keywords entered by the user-entered keywords, a field "Did you mean:" is displayed above the result list, in which an alternative search suggestion is offered.

Automatic search expansion

If this function is configured, in addition to the terms entered by the user, the alternative search suggestion will also be searched.

Configuration

Multi-word capacity of the term lexicon

On the "Indices" tab there is a section at the bottom called "Global Index Settings", which contains a sub-section with “Term Lexicon Settings".

These word combinations are then preferred in both the alternative search suggestions as well as in the automatic search extension for calculating the alternatives.

“Multi Lingual Stopword Vocabulary Path Pattern“: Here a path pattern is specified with which the CSV files that contain stopwords can be obtained.

The placeholder {{lang}} is replaced by the corresponding language.

These stopwords are excluded from the term lexicon.

Here the default language is specified in the form of an i18n-identifier. This value is then used as the replacement for the {{lang}} placeholder.

The metadate mes:lang is used to populate the placeholder {{lang}}.

The following properties can be configured for Term Lexicon:

"Maximum Word NGram Length“: If a value greater than 1 is set, for example 3, adjacent words are collected and stored during the inversion of the index:

Single words with value > = 1

Additional adjacent pairs of words with a value > = 2

Additional adjacent word triplets with a value of >= 3

Etc.

“Full Lexicon Maximum Word NGram Length”: set maximum ngrams length in the full lexicon.

“Invert Maximum Unique Terms per Document”: stop document invertion on reaching the specified maximum unique terms number in the document.

“Limit Char NGrams to Maximum Unique Char NGrams per Document”: maximum number of unique character ngrams to store per document.

“Limit Lexicon to Maximum Unique Terms per Document”: maximum number of unique terms in full lexicon to store per document.

The Term Lexicon settings can additionally be overwritten for each index:

Activation of the automatic search expansion

On the "Client Services" tab (after clicking on the "Advanced Settings" field) under "Query Settings", you’ll find a box called "Enable Query Expansion for Similar Terms", which can be used to turn on the automatic search extension. By default, this field is turned off.