sqlite - Get values set in SQL -

i have kind of table, on sqlite database :

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is there way different values username column, ie getting - in example - user1 user2 user3 without others informations ?

thanks.

both queries yield same result:

select   username   mytable group username

select distinct   username   mytable

the difference can add aggregate functions username group count(*) see how many times particular username appears in table.

UV code