I want to select from a test ride table the data of the last Right
Curve. I can do that by the select as given below. My problem is that
this select is quite inefficient, because the same basic select is
performed twice (once to obtain the time tag and once to obtain the
measurement data).
In cases of heavily joined, more complex selects the same select has to
be repeated almost exactly. I have the feeling that this can be solved
more elegant. Any idea's?
create table test_ride (
time number,
event_type varchar2(10),
speed number
);
--
insert into test_ride values ( 1.20, 'curve_L', 90.2);
insert into test_ride values (11.45, 'curve_R', 89.6);
insert into test_ride values (21.80, 'brake' , 102.2);
insert into test_ride values (21.98, 'curve_R', 79.3);
insert into test_ride values (41.99, 'curve_R', 60.1);
insert into test_ride values (41.03, 'curve_L', 69.7);
insert into test_ride values (51.32, 'curve_R', 122.3);
insert into test_ride values (51.20, 'curve_L', 128.9);
insert into test_ride values (51.65, 'brake' , 93.1);
--
select *
from test_ride
where time = (
select MAX(time)
from test_ride
where event_type = 'curve_R'
)
and event_type = 'curve_R'
;
Received on Wed Apr 19 2006 - 10:08:20 CDT
