Solr - Return random results (Sort by Random)

Question

In Solr, Whats the best approach to order results by random?, basically needs to pick some records at random.

Answer 1

In latest Solr, nothing need to do with schema. Just add below sorting and it will give random result set.

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//Below is to get rendom string
$randString = mt_rand();        
$query->addSort('random_'.$randString, $query::SORT_DESC);

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Answer 2

Use a RandomSortField. There's an example in the bundled schema.xml in example directory (under solr):

<dynamicField name="random_*" type="random" />

Sort your result list by the field random_<seed>, where you replace <seed> with a randomly generated value (but use the same value if you're paginating through the result, as it will give you a stable sort based on the field name).