????????????Oracle??????????????????
???????????? ???????[ 2015/1/5 13:44:04 ] ????????Oracle ????? ???????
declare
i integer;
int1 integer;
t1 number;
t2 number;
t_all number;
t_select number;
execute_count number := 10;
function getnumfromtimestamp(iTime timestamp) return number is
Result number;
v_hour number;
v_minute number;
v_second number;
v_millisecond number;
begin
v_hour := EXTRACT(hour from iTime);
v_minute := EXTRACT(minute from iTime);
v_second := EXTRACT(second from iTime);
Result := (v_hour + 1) * 3600 + (v_minute + 1) * 60 + v_second;
return(Result);
end;
begin
select count(*)
into int1
from (select rn
from (select (mod(rownum?? 3) * 3 - 1) * 1000000 + rownum rn
from dual
connect by rownum <= 1000000
order by rn) c
where rownum + 1 < 10000000);
t1 := getnumfromtimestamp(systimestamp);
for i in 1 .. execute_count loop
select count(*)
into int1
from (select rn
from (select (mod(rownum?? 3) * 3 - 1) * 1000000 + rownum rn
from dual
connect by rownum <= 1000000
order by rn) c
where rownum + 1 < 10000000);
end loop;
t2 := getnumfromtimestamp(systimestamp);
t_all := t2 - t1;
select count(*)
into int1
from (select rn
from (select (mod(rownum?? 3) * 3 - 1) * 1000000 + rownum rn
from dual
connect by rownum <= 1000000) c
where rownum + 1 < 10000000);
t1 := getnumfromtimestamp(systimestamp);
for i in 1 .. execute_count loop
select count(*)
into int1
from (select rn
from (select (mod(rownum?? 3) * 3 - 1) * 1000000 + rownum rn
from dual
connect by rownum <= 1000000) c
where rownum + 1 < 10000000);
end loop;
t2 := getnumfromtimestamp(systimestamp);
t_select := t2 - t1;
dbms_output.put_line('sort_times:' ||
trunc(18792428 / 1000 / ((t_all - t_select))));
end;
/
|
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