这个top sql的脚本是什么意思呐？解决思路

--sidselect l.sid sid,       substr(opname, 1, 15) opname,       target,       trunc((sofar / totalwork) * 100) pct,       to_char(60 * sofar * 8192 /               (24 * 60 * (last_update_time - start_time)) / 1024 / 1024 / 60,               '9999.0') rate,       elapsed_seconds / 60 es,       time_remaining / 60 tr,       program,       machine  from v$session_longops l, v$session s where time_remaining > 0   and l.sid = s.sid order by start_time;--sqlselect l.sid sid,       q.sql_text sql,       substr(opname, 1, 15) opname,       target,       trunc((sofar / totalwork) * 100) pct,       to_char(60 * sofar * 8192 /               (24 * 60 * (last_update_time - start_time)) / 1024 / 1024 / 60,               '9999.0') rate,       elapsed_seconds / 60 es,       time_remaining / 60 tr,       program,       machine  from v$session_longops l, v$session s, v$sql q where time_remaining > 0   and l.sid = s.sid   and s.sql_id = q.sql_id order by start_time;