Re: How to remove duplicates in an array and maintain the order? - Mailing list pgsql-sql

Shaozhong SHI schrieb am 08.07.2023 um 17:30:
> How to remove duplicated values in an array and maintain the order?

You can use distinct on ()

select array_agg(val order by idx)
from (
   select distinct on (val) val, idx
   from unnest(array[7,7,5,6,2,2,3,8,7,5,4,1,5]) with ordinality as t(val,idx)
   order by val, idx
) x


This picks the first occurrance of each element.
If you want to get the last occurrance of each value use "order by val, idx desc" in the inner select