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Thread: Updated RUM-index and support for bigint as part of index

Updated RUM-index and support for bigint as part of index

From

Andreas Joseph Krogh

Date:

02 August 2016, 21:08:40

Hi.

I see the RUM-index is updated, which is great!

I wonder, to be able to sort by timestamp one has to create the index like this:

CREATE INDEX rumidx ON origo_email_delivery USING rum (fts_all rum_tsvector_timestamp_ops, received_timestamp)     WITH (attach = 'received_timestamp', TO = 'fts_all', order_by_attach = TRUE );

Then, to be able to use the index for sorting by the "received_timestamp"-column one has to issue a query like this:

EXPLAIN ANALYZE SELECT
                    del.entity_id,                    del.subject,                    del.received_timestamp,                    fts_all <=> to_tsquery('simple', 'andreas&kr') AS rank                FROM origo_email_delivery del                WHERE del.fts_all @@ to_tsquery('simple', 'andreas&kr')                ORDER BY '2000-01-01' :: TIMESTAMP <=> del.received_timestamp                LIMIT 10;

                                                                    QUERY PLAN                                                                    
--------------------------------------------------------------------------------------------------------------------------------------------------
 Limit  (cost=14.40..26.47 rows=10 width=89) (actual time=10.908..10.952 rows=10 loops=1)   ->  Index Scan using rumidx on origo_email_delivery del  (cost=14.40..3221.22 rows=2657 width=89) (actual time=10.906..10.947 rows=10 loops=1)         Index Cond: (fts_all @@ '''andreas'' & ''kr'''::tsquery)         Order By: (received_timestamp <=> '2000-01-01 00:00:00'::timestamp without time zone) Planning time: 0.491 ms Execution time: 11.010 ms
(6 rows)

The ORDER BY part seems strange; It seems one has to find a value "lower than any other value" to use as a kind of base, why is this necessary? It also seems that in order to be able to sort DESC one has to provide a timestamp value "higher than any other value", is this correct?

It would be great if the docs explained this.

I really miss the opportunity to include a BIGINT as part of the index, so that the WHERE-clause could be like this:

WHERE del.fts_all @@ to_tsquery('simple', 'andreas&kr') AND del.folder_id IN (1,2,3)

Having this would be perfect for my use-case searching in email in folders, sorted by received_date, and having it use ONE index.

Will this be supported?

Thanks.

Andreas Joseph Krogh

CTO / Partner - Visena AS

Mobile: +47 909 56 963

andreas@visena.com

www.visena.com

Attachment

msg-1550305-3.png

Re: Updated RUM-index and support for bigint as part of index

From

Artur Zakirov

Date:

06 August 2016, 21:54:46

Hello,

2016-08-02 21:08 GMT+03:00 Andreas Joseph Krogh <andreas@visena.com>:

The ORDER BY part seems strange; It seems one has to find a value "lower than any other value" to use as a kind of base, why is this necessary? It also seems that in order to be able to sort DESC one has to provide a timestamp value "higher than any other value", is this correct?

It would be great if the docs explained this.

We will write more detailed documentation for RUM.

I really miss the opportunity to include a BIGINT as part of the index, so that the WHERE-clause could be like this:

WHERE del.fts_all @@ to_tsquery('simple', 'andreas&kr') AND del.folder_id IN (1,2,3)

Having this would be perfect for my use-case searching in email in folders, sorted by received_date, and having it use ONE index.

Will this be supported?

We have a plan to use generic types to able to include bigint, timestamp and other types as part of index. But I cant tell date of it.

Artur Zakirov

Postgres Professional: http://www.postgrespro.com

Russian Postgres Company

Re: Updated RUM-index and support for bigint as part of index

From

Oleg Bartunov

Date:

07 August 2016, 09:27:38

On Tue, Aug 2, 2016 at 9:08 PM, Andreas Joseph Krogh <andreas@visena.com> wrote:

Hi.

I see the RUM-index is updated, which is great!

I wonder, to be able to sort by timestamp one has to create the index like this:

CREATE INDEX rumidx ON origo_email_delivery USING rum (fts_all rum_tsvector_timestamp_ops, received_timestamp)     WITH (attach = 'received_timestamp', TO = 'fts_all', order_by_attach = TRUE );

Then, to be able to use the index for sorting by the "received_timestamp"-column one has to issue a query like this:

EXPLAIN ANALYZE SELECT
                    del.entity_id,                    del.subject,                    del.received_timestamp,                    fts_all <=> to_tsquery('simple', 'andreas&kr') AS rank                FROM origo_email_delivery del                WHERE del.fts_all @@ to_tsquery('simple', 'andreas&kr')                ORDER BY '2000-01-01' :: TIMESTAMP <=> del.received_timestamp                LIMIT 10;

                                                                    QUERY PLAN                                                                    
--------------------------------------------------------------------------------------------------------------------------------------------------
 Limit  (cost=14.40..26.47 rows=10 width=89) (actual time=10.908..10.952 rows=10 loops=1)   ->  Index Scan using rumidx on origo_email_delivery del  (cost=14.40..3221.22 rows=2657 width=89) (actual time=10.906..10.947 rows=10 loops=1)         Index Cond: (fts_all @@ '''andreas'' & ''kr'''::tsquery)         Order By: (received_timestamp <=> '2000-01-01 00:00:00'::timestamp without time zone) Planning time: 0.491 ms Execution time: 11.010 ms
(6 rows)

have you considered <=| and |=> operators ? <=> in ORDER BY works like KNN.

It would be great if the docs explained this.

I really miss the opportunity to include a BIGINT as part of the index, so that the WHERE-clause could be like this:

WHERE del.fts_all @@ to_tsquery('simple', 'andreas&kr') AND del.folder_id IN (1,2,3)

Having this would be perfect for my use-case searching in email in folders, sorted by received_date, and having it use ONE index.

Will this be supported?

Thanks.

--
Andreas Joseph Krogh
CTO / Partner - Visena AS
Mobile: +47 909 56 963
andreas@visena.com
www.visena.com

Attachment

msg-1550308-3.png

Re: Updated RUM-index and support for bigint as part of index

From

Andreas Joseph Krogh

Date:

07 August 2016, 09:42:51

På lørdag 06. august 2016 kl. 20:54:32, skrev Artur Zakirov <a.zakirov@postgrespro.ru>:

Hello,
2016-08-02 21:08 GMT+03:00 Andreas Joseph Krogh <andreas@visena.com>:
The ORDER BY part seems strange; It seems one has to find a value "lower than any other value" to use as a kind of base, why is this necessary? It also seems that in order to be able to sort DESC one has to provide a timestamp value "higher than any other value", is this correct?
It would be great if the docs explained this.
We will write more detailed documentation for RUM.

Great!

I really miss the opportunity to include a BIGINT as part of the index, so that the WHERE-clause could be like this:

WHERE del.fts_all @@ to_tsquery('simple', 'andreas&kr') AND del.folder_id IN (1,2,3)

Having this would be perfect for my use-case searching in email in folders, sorted by received_date, and having it use ONE index.

Will this be supported?

We have a plan to use generic types to able to include bigint, timestamp and other types as part of index.

Does this eliminate the need for a btree_rum equivalent of btree_gin, being that the RUM-index will handle all "btree-able" datatypes?

But I cant tell date of it.

I understand.

Do you think it will be done by the time 9.6 is released?

Thanks.

Andreas Joseph Krogh

CTO / Partner - Visena AS

Mobile: +47 909 56 963

andreas@visena.com

www.visena.com

Attachment

msg-1550311-3.png

Re: Updated RUM-index and support for bigint as part of index

From

Andreas Joseph Krogh

Date:

07 August 2016, 11:05:58

På søndag 07. august 2016 kl. 08:27:06, skrev Oleg Bartunov <obartunov@gmail.com>:

[snip]
have you considered <=| and |=> operators ? <=> in ORDER BY works like KNN.

I don't get how these operators should work. Neither give me the expected results.

Using <=>

SELECT
    del.entity_id,    del.folder_id,    del.received_timestamp
FROM origo_email_delivery del
WHERE del.fts_all @@ to_tsquery('simple', 'andreas:*&jose:*')
ORDER BY '2000-01-01' :: TIMESTAMP <=> del.received_timestamp
LIMIT 10;

entity_id | folder_id |   received_timestamp
-----------+-----------+-------------------------
  1224278 |   1068087 | 2015-08-17 23:53:26
  1224382 |   1068087 | 2015-08-18 03:07:55
  1224404 |   1068087 | 2015-08-18 03:49:02
  1505713 |     48496 | 2015-10-27 14:51:45
   142132 |     66658 | 2012-12-03 14:14:05.488
   122565 |     90115 | 2012-11-20 15:41:04.936
   200744 |     66655 | 2013-01-28 21:47:44.561
  1445927 |    888665 | 2015-09-29 00:26:56
   123671 |     83509 | 2012-11-21 14:16:26.448
  1129928 |     66658 | 2015-05-09 08:39:14.128
(10 rows)

Using <=|

SELECT
    del.entity_id,    del.folder_id,    del.received_timestamp
FROM origo_email_delivery del
WHERE del.fts_all @@ to_tsquery('simple', 'andreas:*&jose:*')
ORDER BY '2000-01-01' :: TIMESTAMP <=| del.received_timestamp
LIMIT 10;

Neither are ordered by received_timestamp

Can you explain how to get ORDER BY received_timestamp DESC?

Thanks.

Andreas Joseph Krogh

CTO / Partner - Visena AS

Mobile: +47 909 56 963

andreas@visena.com

www.visena.com

Attachment

msg-1550314-3.png

Re: Updated RUM-index and support for bigint as part of index

From

Artur Zakirov

Date:

11 August 2016, 20:13:51

On 07.08.2016 11:05, Andreas Joseph Krogh wrote:
> På søndag 07. august 2016 kl. 08:27:06, skrev Oleg Bartunov
> <obartunov@gmail.com <mailto:obartunov@gmail.com>>:
>
>     [snip]
>     have you considered <=| and |=> operators ? <=> in ORDER BY works
>     like KNN.
>
>
> I don't get how these operators should work. Neither give me the
> expected results.
>
> Using <=>
>
>
> SELECT del.entity_id, del.folder_id, del.received_timestamp FROM
> origo_email_delivery del WHERE del.fts_all @@ to_tsquery('simple',
> 'andreas:*&jose:*') ORDER BY '2000-01-01' :: TIMESTAMP <=>
> del.received_timestamp LIMIT 10;
>
>  entity_id | folder_id |   received_timestamp
> -----------+-----------+-------------------------
>   1224278 |   1068087 | 2015-08-17 23:53:26
>   1224382 |   1068087 | 2015-08-18 03:07:55
>   1224404 |   1068087 | 2015-08-18 03:49:02
>   1505713 |     48496 | 2015-10-27 14:51:45
>    142132 |     66658 | 2012-12-03 14:14:05.488
>    122565 |     90115 | 2012-11-20 15:41:04.936
>    200744 |     66655 | 2013-01-28 21:47:44.561
>   1445927 |    888665 | 2015-09-29 00:26:56
>    123671 |     83509 | 2012-11-21 14:16:26.448
>   1129928 |     66658 | 2015-05-09 08:39:14.128
> (10 rows)
>
>
> Using <=|
>
> SELECT del.entity_id, del.folder_id, del.received_timestamp FROM
> origo_email_delivery del WHERE del.fts_all @@ to_tsquery('simple',
> 'andreas:*&jose:*') ORDER BY '2000-01-01' :: TIMESTAMP <=|
> del.received_timestamp LIMIT 10;
>
>
>  entity_id | folder_id |   received_timestamp
> -----------+-----------+-------------------------
>   1224278 |   1068087 | 2015-08-17 23:53:26
>   1224382 |   1068087 | 2015-08-18 03:07:55
>   1224404 |   1068087 | 2015-08-18 03:49:02
>   1505713 |     48496 | 2015-10-27 14:51:45
>    142132 |     66658 | 2012-12-03 14:14:05.488
>    122565 |     90115 | 2012-11-20 15:41:04.936
>    200744 |     66655 | 2013-01-28 21:47:44.561
>   1445927 |    888665 | 2015-09-29 00:26:56
>    123671 |     83509 | 2012-11-21 14:16:26.448
>   1129928 |     66658 | 2015-05-09 08:39:14.128
> (10 rows)
>
>
> Neither are ordered by received_timestamp
>
> Can you explain how to get ORDER BY received_timestamp DESC?
>
> Thanks.
>
> --
> *Andreas Joseph Krogh*
> CTO / Partner - Visena AS
> Mobile: +47 909 56 963
> andreas@visena.com <mailto:andreas@visena.com>
> www.visena.com <https://www.visena.com>
> <https://www.visena.com>
>

Do you need simple ordering by received_timestamp column? Not ordering
by distance between received_timestamp and some date?

Then you can use simple "ORDER BY received_timestamp". For example, we
have data:

=# SELECT * FROM test;
  id |     fts     |        received
----+-------------+-------------------------
   1 | 'andreas':1 | 2015-08-17 23:53:26
   2 | 'andreas':1 | 2015-08-18 03:07:55
   3 | 'andreas':1 | 2015-08-18 03:49:02
   4 | 'andreas':1 | 2012-12-03 14:14:05.488
   5 | 'andreas':1 | 2012-11-20 15:41:04.936
   6 | 'andreas':1 | 2013-01-28 21:47:44.561
   6 | 'andreas':1 | 2015-09-29 00:26:56
   7 | 'andreas':1 | 2012-11-21 14:16:26.448
   8 | 'andreas':1 | 2015-05-09 08:39:14.128
(9 rows)

I created index:

CREATE INDEX rumidx ON test USING rum (fts rum_tsvector_timestamp_ops,
received) WITH (attach = 'received', to = 'fts');

Then we can execute queries:

=# SELECT id, received FROM test WHERE fts @@ to_tsquery('simple',
'andreas') ORDER BY received LIMIT 8;
  id |        received
----+-------------------------
   5 | 2012-11-20 15:41:04.936
   7 | 2012-11-21 14:16:26.448
   4 | 2012-12-03 14:14:05.488
   6 | 2013-01-28 21:47:44.561
   8 | 2015-05-09 08:39:14.128
   1 | 2015-08-17 23:53:26
   2 | 2015-08-18 03:07:55
   3 | 2015-08-18 03:49:02
(8 rows)

=# SELECT id, received FROM test WHERE fts @@ to_tsquery('simple',
'andreas') ORDER BY received DESC LIMIT 8;
  id |        received
----+-------------------------
   6 | 2015-09-29 00:26:56
   3 | 2015-08-18 03:49:02
   2 | 2015-08-18 03:07:55
   1 | 2015-08-17 23:53:26
   8 | 2015-05-09 08:39:14.128
   6 | 2013-01-28 21:47:44.561
   4 | 2012-12-03 14:14:05.488
   7 | 2012-11-21 14:16:26.448
(8 rows)

Operators <=>, |=>, <=| you can use to order by nearest date to specific
date:

=# SELECT id, received, received <=> '2013-01-01' AS rank FROM test
WHERE fts @@ to_tsquery('simple', 'andreas') ORDER BY received <=>
'2013-01-01' LIMIT 8;
  id |        received         |     rank
----+-------------------------+--------------
   6 | 2013-01-28 21:47:44.561 |  2411264.561
   4 | 2012-12-03 14:14:05.488 |  2454354.512
   7 | 2012-11-21 14:16:26.448 |  3491013.552
   5 | 2012-11-20 15:41:04.936 |  3572335.064
   8 | 2015-05-09 08:39:14.128 | 74162354.128
   1 | 2015-08-17 23:53:26     |     82857206
   2 | 2015-08-18 03:07:55     |     82868875
   3 | 2015-08-18 03:49:02     |     82871342
(8 rows)

=# SELECT id, received, received <=> '2013-01-01' AS rank FROM test
WHERE fts @@ to_tsquery('simple', 'andreas') ORDER BY received <=>
'2013-01-01' DESC LIMIT 8;
  id |        received         |     rank
----+-------------------------+--------------
   6 | 2015-09-29 00:26:56     |     86488016
   3 | 2015-08-18 03:49:02     |     82871342
   2 | 2015-08-18 03:07:55     |     82868875
   1 | 2015-08-17 23:53:26     |     82857206
   8 | 2015-05-09 08:39:14.128 | 74162354.128
   5 | 2012-11-20 15:41:04.936 |  3572335.064
   7 | 2012-11-21 14:16:26.448 |  3491013.552
   4 | 2012-12-03 14:14:05.488 |  2454354.512
(8 rows)

I hope this is what you want.

--
Artur Zakirov
Postgres Professional: http://www.postgrespro.com
Russian Postgres Company

Re: Updated RUM-index and support for bigint as part of index

From

Andreas Joseph Krogh

Date:

11 August 2016, 23:33:59

På torsdag 11. august 2016 kl. 19:13:10, skrev Artur Zakirov <a.zakirov@postgrespro.ru>:

On 07.08.2016 11:05, Andreas Joseph Krogh wrote:
> På søndag 07. august 2016 kl. 08:27:06, skrev Oleg Bartunov
> <obartunov@gmail.com <mailto:obartunov@gmail.com>>:
>
> [snip]
> have you considered <=| and |=> operators ? <=> in ORDER BY works
> like KNN.
>
>
> I don't get how these operators should work. Neither give me the
> expected results.
>
> Using <=>
>
>
> SELECT del.entity_id, del.folder_id, del.received_timestamp FROM
> origo_email_delivery del WHERE del.fts_all @@ to_tsquery('simple',
> 'andreas:*&jose:*') ORDER BY '2000-01-01' :: TIMESTAMP <=>
> del.received_timestamp LIMIT 10;
>
> entity_id | folder_id | received_timestamp
> -----------+-----------+-------------------------
> 1224278 | 1068087 | 2015-08-17 23:53:26
> 1224382 | 1068087 | 2015-08-18 03:07:55
> 1224404 | 1068087 | 2015-08-18 03:49:02
> 1505713 | 48496 | 2015-10-27 14:51:45
> 142132 | 66658 | 2012-12-03 14:14:05.488
> 122565 | 90115 | 2012-11-20 15:41:04.936
> 200744 | 66655 | 2013-01-28 21:47:44.561
> 1445927 | 888665 | 2015-09-29 00:26:56
> 123671 | 83509 | 2012-11-21 14:16:26.448
> 1129928 | 66658 | 2015-05-09 08:39:14.128
> (10 rows)
>
>
> Using <=|
>
> SELECT del.entity_id, del.folder_id, del.received_timestamp FROM
> origo_email_delivery del WHERE del.fts_all @@ to_tsquery('simple',
> 'andreas:*&jose:*') ORDER BY '2000-01-01' :: TIMESTAMP <=|
> del.received_timestamp LIMIT 10;
>
>
> entity_id | folder_id | received_timestamp
> -----------+-----------+-------------------------
> 1224278 | 1068087 | 2015-08-17 23:53:26
> 1224382 | 1068087 | 2015-08-18 03:07:55
> 1224404 | 1068087 | 2015-08-18 03:49:02
> 1505713 | 48496 | 2015-10-27 14:51:45
> 142132 | 66658 | 2012-12-03 14:14:05.488
> 122565 | 90115 | 2012-11-20 15:41:04.936
> 200744 | 66655 | 2013-01-28 21:47:44.561
> 1445927 | 888665 | 2015-09-29 00:26:56
> 123671 | 83509 | 2012-11-21 14:16:26.448
> 1129928 | 66658 | 2015-05-09 08:39:14.128
> (10 rows)
>
>
> Neither are ordered by received_timestamp
>
> Can you explain how to get ORDER BY received_timestamp DESC?
>
> Thanks.
>
> --
> *Andreas Joseph Krogh*
> CTO / Partner - Visena AS
> Mobile: +47 909 56 963
> andreas@visena.com <mailto:andreas@visena.com>
> www.visena.com <https://www.visena.com>
> <https://www.visena.com>
>

Do you need simple ordering by received_timestamp column? Not ordering
by distance between received_timestamp and some date?

Then you can use simple "ORDER BY received_timestamp". For example, we
have data:

=# SELECT * FROM test;
id | fts | received
----+-------------+-------------------------
1 | 'andreas':1 | 2015-08-17 23:53:26
2 | 'andreas':1 | 2015-08-18 03:07:55
3 | 'andreas':1 | 2015-08-18 03:49:02
4 | 'andreas':1 | 2012-12-03 14:14:05.488
5 | 'andreas':1 | 2012-11-20 15:41:04.936
6 | 'andreas':1 | 2013-01-28 21:47:44.561
6 | 'andreas':1 | 2015-09-29 00:26:56
7 | 'andreas':1 | 2012-11-21 14:16:26.448
8 | 'andreas':1 | 2015-05-09 08:39:14.128
(9 rows)

I created index:

CREATE INDEX rumidx ON test USING rum (fts rum_tsvector_timestamp_ops,
received) WITH (attach = 'received', to = 'fts');

Then we can execute queries:

=# SELECT id, received FROM test WHERE fts @@ to_tsquery('simple',
'andreas') ORDER BY received LIMIT 8;
id | received
----+-------------------------
5 | 2012-11-20 15:41:04.936
7 | 2012-11-21 14:16:26.448
4 | 2012-12-03 14:14:05.488
6 | 2013-01-28 21:47:44.561
8 | 2015-05-09 08:39:14.128
1 | 2015-08-17 23:53:26
2 | 2015-08-18 03:07:55
3 | 2015-08-18 03:49:02
(8 rows)

=# SELECT id, received FROM test WHERE fts @@ to_tsquery('simple',
'andreas') ORDER BY received DESC LIMIT 8;
id | received
----+-------------------------
6 | 2015-09-29 00:26:56
3 | 2015-08-18 03:49:02
2 | 2015-08-18 03:07:55
1 | 2015-08-17 23:53:26
8 | 2015-05-09 08:39:14.128
6 | 2013-01-28 21:47:44.561
4 | 2012-12-03 14:14:05.488
7 | 2012-11-21 14:16:26.448
(8 rows)

Yes, this gives the correct result, but the whole motivation for using RUM-index is for the query to use the same index for ORDER BY, as it seems to do using the <=> operator.

The query you gave above does not the index for sorting AFAIU.

Operators <=>, |=>, <=| you can use to order by nearest date to specific
date:
[snip]

I hope this is what you want.

I still don't understand how my query which had ORDER BY '2000-01-01' :: TIMESTAMP <=> del.received_timestamp

can produce the following ordering:

How can "nearest date to specific date" produce this ordering when the specific date si 2000-01-01?

Thanks for explaining.

Andreas Joseph Krogh

CTO / Partner - Visena AS

Mobile: +47 909 56 963

andreas@visena.com

www.visena.com

Attachment

msg-1550322-3.png

Re: Updated RUM-index and support for bigint as part of index

From

Oleg Bartunov

Date:

25 August 2016, 19:13:01

Andreas,

sorry for delay,

it looks like a bug to me, could you please, share your dataset with me, so I could reproduce the behaviour.

Regards,

Oleg

On Sun, Aug 7, 2016 at 11:05 AM, Andreas Joseph Krogh <andreas@visena.com> wrote:

På søndag 07. august 2016 kl. 08:27:06, skrev Oleg Bartunov <obartunov@gmail.com>:
[snip]
have you considered <=| and |=> operators ? <=> in ORDER BY works like KNN.

I don't get how these operators should work. Neither give me the expected results.

Using <=>
SELECT
    del.entity_id,    del.folder_id,    del.received_timestamp
FROM origo_email_delivery del
WHERE del.fts_all @@ to_tsquery('simple', 'andreas:*&jose:*')
ORDER BY '2000-01-01' :: TIMESTAMP <=> del.received_timestamp
LIMIT 10;
entity_id | folder_id |   received_timestamp
-----------+-----------+-------------------------
  1224278 |   1068087 | 2015-08-17 23:53:26
  1224382 |   1068087 | 2015-08-18 03:07:55
  1224404 |   1068087 | 2015-08-18 03:49:02
  1505713 |     48496 | 2015-10-27 14:51:45
   142132 |     66658 | 2012-12-03 14:14:05.488
   122565 |     90115 | 2012-11-20 15:41:04.936
   200744 |     66655 | 2013-01-28 21:47:44.561
  1445927 |    888665 | 2015-09-29 00:26:56
   123671 |     83509 | 2012-11-21 14:16:26.448
  1129928 |     66658 | 2015-05-09 08:39:14.128
(10 rows)

Using <=|
SELECT
    del.entity_id,    del.folder_id,    del.received_timestamp
FROM origo_email_delivery del
WHERE del.fts_all @@ to_tsquery('simple', 'andreas:*&jose:*')
ORDER BY '2000-01-01' :: TIMESTAMP <=| del.received_timestamp
LIMIT 10; 
entity_id | folder_id |   received_timestamp
-----------+-----------+-------------------------
  1224278 |   1068087 | 2015-08-17 23:53:26
  1224382 |   1068087 | 2015-08-18 03:07:55
  1224404 |   1068087 | 2015-08-18 03:49:02
  1505713 |     48496 | 2015-10-27 14:51:45
   142132 |     66658 | 2012-12-03 14:14:05.488
   122565 |     90115 | 2012-11-20 15:41:04.936
   200744 |     66655 | 2013-01-28 21:47:44.561
  1445927 |    888665 | 2015-09-29 00:26:56
   123671 |     83509 | 2012-11-21 14:16:26.448
  1129928 |     66658 | 2015-05-09 08:39:14.128
(10 rows)

Neither are ordered by received_timestamp

Can you explain how to get ORDER BY received_timestamp DESC?

Thanks.

--
Andreas Joseph Krogh
CTO / Partner - Visena AS
Mobile: +47 909 56 963
andreas@visena.com
www.visena.com