Distinct Attribute

The value of a field whose attribute is set as a distinct attribute will always be unique in the returned documents.

In such a case, there will never be two, or more, occurrences of the same value of that field in the different documents returned by MeiliSearch.

Example

Suppose you have an e-commerce dataset. For an index that contains information about jackets, you may have several identical items in different variations (color or size).

As shown below, you have 3 documents that contain information about the same jacket. One of the jackets is brown, one is black, and the last one is blue.

[
  {
    "id": 1,
    "description": "Leather jacket",
    "brand": "Lee jeans",
    "color": "brown",
    "product_id": "123456"
  },
  {
    "id": 2,
    "description": "Leather jacket",
    "brand": "Lee jeans",
    "color": "black",
    "product_id": "123456"
  },
  {
    "id": 3,
    "description": "Leather jacket",
    "brand": "Lee jeans",
    "color": "blue",
    "product_id": "123456"
  }
]

You may want to ignore the different colors of an item. To do so, you can set product_id as a distinctAttribute.

$ curl
  -X POST 'http://localhost:7700/indexes/jackets/settings' \
  --data '{ "distinctAttribute": "product_id" }'

client.index('jackets').updateSettings({ distinctAttribute: 'product_id' })

client.index('jackets').update_settings({'distinctAttribute': 'product_id'})

$client->index('jackets')->updateDistinctAttribute('product_id');

client.index('jackets').update_distinct_attribute('product_id')

client.Settings("jackets").UpdateDistinctAttribute("product_id")

let jackets: Index = client.get_index("jackets").await.unwrap();
let progress: Progress = jackets.set_distinct_attribute("product_id").await.unwrap();

By setting product_id as a distinct attribute, search requests will never return more than one jacket with the same product_id.

WARNING

If the field does not exist, no error will be thrown.