Search indexes

A search index makes a field searchable through an analyzer that has already been defined. This page covers defining one, why each index takes a single field, and the parse error that follows from listing several.

Defining an index that uses an analyzer

Once a search analyzer is defined, it can be applied to the fields of a table to make them searchable by defining an index that uses the FULLTEXT ANALYZER clause.

DEFINE ANALYZER my_analyzer
  TOKENIZERS class
  FILTERS lowercase, ascii;

DEFINE INDEX body_index 
  ON TABLE article
  FIELDS body
  FULLTEXT ANALYZER my_analyzer;

DEFINE INDEX title_index
  ON TABLE article
  FIELDS title 
  FULLTEXT ANALYZER my_analyzer;

An index can only be defined on a single field (column).

DEFINE ANALYZER my_analyzer
  TOKENIZERS class
  FILTERS lowercase, ascii;

DEFINE INDEX body_index 
  ON TABLE article 
  FIELDS body, title 
  FULLTEXT ANALYZER my_analyzer;

'Parse error: Expected one column, found 2
 //- [5:55]
  |
5 | ...LDS body, title FULLTEXT ANALYZER my_analyzer;
  |              ^^^^^
'

For querying with @@, BM25, and highlights, continue to Scoring and ranking.