How to select distinct field values using Solr?

Question

I would like to do the equivalent of this SQL but with Solr as my data store.

SELECT
   DISTINCT txt
FROM
   my_table;

What syntax would fo

Answer 1

I would store the substring in a different field (let's call in txt_substring), then facet on txt_substring as CraftyFella showed.

Normally I'd use the n-gram tokenizer, but I don't think you can facet on that.