RethinkDB filtering Object Array

Question

I'm new to rethinkdb and I wanted to filter something like... get all with Kiwi or Strawberry as preferred fruit

{
    "id":  "65dbaa34-f7d5-4a25-b01f-682032fc6e05" ,
    "fruits": {
        "favorite":  "Mango" ,
        "preferred": [
                        "Kiwi" ,
                        "Watermelon"
                    ]
    }
}

I tried something like this after reading contains doc:

r.db('appname').table('food')
 .filter(r.row('fruits').contains(function(doc) {
   return doc('preferred').contains('Kiwi');
 }))

And I'm getting a e: Cannot convert OBJECT to SEQUENCE in: error.

dalanmiller · Accepted Answer · 2019-04-08T23:25:21.287

3

This is what you're looking for:

r.db('appname').table('food')
  .filter((row) => { 
    r.or( // Returns true if any of the following are true
      row('fruits')('preferred').contains('Kiwi'),
      row('fruits')('preferred').contains('Strawberry')
    )   
  });

You should know as well, that you can create your own index that calculates this for you, then you'd be able to do a .getAll query using your custom index and return all documents that fit this constraint very quickly.

Lastly, for something that would also work but is probably less efficient on large arrays:

r.db("appname").table('food')
  .filter((row) => {
    return row('fruits')('preferred').setIntersection(['Kiwi', 'Strawberry']).count().gt(0) 
  })

edited Apr 08 '19 at 23:25

answered Sep 09 '16 at 22:35

dalanmiller

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Thank you upon testing, this worked :). The only catch on this solution is if "fruits.preferred" form is not consistent e.g if it's "fruits": "" when no favorite and preferred is set. The query will produce an error. Do you have a technique for such scenarios? Or just having an empty fruits: {favorite: "", preferred: []} the solution? – Woppi Sep 13 '16 at 09:21
I figured it out. I need to use hasFields. :) – Woppi Sep 14 '16 at 03:27

RethinkDB filtering Object Array

1 Answers1