for schema in 'public' 'firstschema' 'secondschema'
do
    for tbl in `psql -h hostname -U postgres -qAt -c "select tablename from pg_tables where schemaname = '$schema';" bddname`
    do
        psql -h hostname -U postgres -c "alter table ${schema}.$tbl owner to username" bddname
    done
done

for schema in 'public' 'firstschema' 'secondschema'
do
    for ...

SELECT depname, empno, salary, rank() OVER (PARTITION BY depname ORDER BY salary DESC) FROM empsalary;