On Mon, 27 Sep 1999, Tom Lane wrote:
> Zakkr <zakkr@zf.jcu.cz> writes:
> > abil=> select '{"aaa"}'::_text union select '{"bbb"}'::_text;
> > ERROR: Unable to identify an ordering operator '<' for type '_text'
> > Use an explicit ordering operator or modify the query
>
> Depending on what you're trying to do, UNION ALL might be an adequate
> workaround. UNION is defined to remove duplicates, so it has to sort
> the results of the union'ed queries, which requires an ordering
> operator. UNION ALL just appends the two query results together...
>
Yes, UNION ALL is good resolution for me. Thank Tom.
> In the long run we probably ought to think about providing ordering
> operators for array types.
..hmm :-))