Here is a little test example. It seems that the second order by
condition is not working - in this case datetime.
create table arb_test (
client_id integer,
arbnum integer);
insert into arb_test values (2,1);
insert into arb_test values (2,33);
insert into arb_test values (2,6);
insert into arb_test values (2,76);
insert into arb_test values (2,111);
insert into arb_test values (2,10);
insert into arb_test values (2,55);
insert into arb_test values (7,12);
insert into arb_test values (7,6);
insert into arb_test values (7,144);
insert into arb_test values (7,63);
insert into arb_test values (7,87);
insert into arb_test values (7,24);
insert into arb_test values (7,22);
insert into arb_test values (1,14);
insert into arb_test values (1,23);
insert into arb_test values (1,67);
insert into arb_test values (1,90);
insert into arb_test values (1,2);
insert into arb_test values (1,5);
insert into arb_test values (5,8);
insert into arb_test values (5,42);
insert into arb_test values (5,77);
insert into arb_test values (5,9);
insert into arb_test values (5,89);
insert into arb_test values (5,23);
insert into arb_test values (5,11);
DROP SEQUENCE if exists seq1;
DROP SEQUENCE if exists seq2;
CREATE TEMPORARY SEQUENCE seq1 CACHE 1000;
CREATE TEMPORARY SEQUENCE seq2 CACHE 1000;
select a.client_id, b.arbnum, a.arbnum as previousarbnum, (b.arbnum -
a.arbnum) as diffarbnum from
(select nextval('seq1') as s, client_id, arbnum from arb_test
order by client_id, arbnum OFFSET 0) as a
inner join
(select nextval('seq2') as s, client_id, arbnum from arb_test
order by client_id, arbnum OFFSET 0) as b
on a.s=(b.s-1) where a.client_id=b.client_id;
--create or replace view arb_view as select * from arb_test order by
client_id, arbnum;
Here are the results:
client_id | arbnum | previousarbnum | diffarbnum
-----------+--------+----------------+------------
1 | 23 | 14 | 9
1 | 67 | 23 | 44
1 | 90 | 67 | 23
1 | 2 | 90 | -88
1 | 5 | 2 | 3
2 | 33 | 1 | 32
2 | 6 | 33 | -27
2 | 76 | 6 | 70
2 | 111 | 76 | 35
2 | 10 | 111 | -101
2 | 55 | 10 | 45
5 | 42 | 8 | 34
5 | 77 | 42 | 35
5 | 9 | 77 | -68
5 | 89 | 9 | 80
5 | 23 | 89 | -66
5 | 11 | 23 | -12
7 | 6 | 12 | -6
7 | 144 | 6 | 138
7 | 63 | 144 | -81
7 | 87 | 63 | 24
7 | 24 | 87 | -63
When I used a sorted view:
create or replace view arb_view as select * from arb_test order by
client_id, arbnum;
and redid it the results are:
client_id | arbnum | previousarbnum | diffarbnum
-----------+--------+----------------+------------
1 | 5 | 2 | 3
1 | 14 | 5 | 9
1 | 23 | 14 | 9
1 | 67 | 23 | 44
1 | 90 | 67 | 23
2 | 6 | 1 | 5
2 | 10 | 6 | 4
2 | 33 | 10 | 23
2 | 55 | 33 | 22
2 | 76 | 55 | 21
2 | 111 | 76 | 35
5 | 9 | 8 | 1
5 | 11 | 9 | 2
5 | 23 | 11 | 12
5 | 42 | 23 | 19
5 | 77 | 42 | 35
5 | 89 | 77 | 12
7 | 12 | 6 | 6
7 | 22 | 12 | 10
7 | 24 | 22 | 2
7 | 63 | 24 | 39
7 | 87 | 63 | 24
7 | 144 | 87 | 57
(23 rows)
This works the way it should.
--drop table arb_test;
--drop view arb_view;
willem
The 'all_client_times' table has 753698 rows. The lagfunc() on the
sorted view returns 753576 rows and appears to work exactly as
needed. Using the function on an unsorted table returns only 686 rows
and is missing a whole lot of data. Running the count query returns
122 - which is correct as the amount of clients that I have. Each
client has between 5 - 7K records each.
The way I see it is for each client there will be one row, namely, the
first in the series, that will not be included in the final results as
it would not have a previous time. With that in mind, if I take my
table row count as 753698 and minus the amount of clients I have,
122, then I should get the number of results as 753576 which is
correct when I use your methods on a sorted table but which is not
correct when I use your methods on an unsorted table.
willem
Adam Rich wrote:
Hi Willem,
for some reason the order by's aren't working.
Could you provide more details? Do you get a specific error message?
only returning 658 rows instead of the 750K.
You should not expect the same row count in both source table and
result set. Even in your example -- you provided 8 source rows, and
4 result rows. You can determine the correct number of results via
"the number of records, related to client_ids having two or more
records in all_client_times, minus one". It may be true that you
have 750k
records but only 658 rows that satisfy this requirement.
What do you get for this query?
select count(*) from ( select client_id, count(*) as rows from
all_client_times group by client_id having count(*) > 1 ) as x
Adam
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