查询多个集合Arangodb

Question

FOR col_name IN ['col_1', 'col_2']

FOR d IN FULLTEXT(col_name, 'label', @value)

RETURN d

does not works

but

FOR d IN FULLTEXT('col_1', 'label', @value)

RETURN d

works fine

I am using arango 3.4.2-1

Answer 1

in general you can query two collections like this:

FOR col1doc IN col_1
  FILTER col1doc.foo == 'bar'
    FOR col2doc IN col_2
      FILTER col1doc.joinfield == col2doc.joinfield
RETURN {col1doc: col1doc, col2doc: col2doc} 

as its documented in the AQL manual for joins

Please note that simple string equalities can be done using FILTER s and don't need fulltext indices.

To the old fulltext index for two collections you can use subqueries like this:

let col1Documents = (FULLTEXT(col_1, 'label', @value))
let col2Documents = (FULLTEXT(col_2, 'label', @value))

RETURN CONCAT(col1Documents, col2Documents)

The more modern way to achieve this would be to use ArangoSearch views which can handle numerous collections.