Thanks Dmitry,

The way I see that works with Firebird an the others engines (Oracle, Postgres) is:

select * from (select "FECH","HECH" from "MOVI" where "HECH"='P' order by "FECH") A1
union
select * from (select "FECH","HECH" from "MOVI" where "HECH"='P' order by "FECH") A2

Also, I can see my other approach does not work in any of the 3 engines.

I was curious ... nothing else.

Regards,

Dany