My table is:
id sub_id datetime resource
---|-----|------------|-------
1 | 10 | 04/03/2009 | 399
2 | 11 | 04/03/2009 | 244
3 | 10 | 04/03/2009 | 555
4 | 10 | 03/03/2009 | 300
5 | 11 | 03/03/2009 | 200
6 | 11 | 03/03/2009 | 500
7 | 11 | 24/12/2008 | 600
8 | 13 | 01/01/2009 | 750
9 | 10 | 01/01/2009 | 760
10 | 13 | 01/01/2009 | 570
11 | 11 | 01/01/2009 | 870
12 | 13 | 01/01/2009 | 670
13 | 13 | 01/01/2009 | 703
14 | 13 | 01/01/2009 | 705
I need to select for each sub_id only 2 times
Result would be:
id sub_id datetime resource
---|-----|------------|-------
1 | 10 | 04/03/2009 | 399
3 | 10 | 04/03/2009 | 555
5 | 11 | 03/03/2009 | 200
6 | 11 | 03/03/2009 | 500
8 | 13 | 01/01/2009 | 750
10 | 13 | 01/01/2009 | 570
How can I achieve this result in postgres ?
Use the window function row_number():
select id, sub_id, datetime, resource
from (
select *, row_number() over (partition by sub_id order by id)
from my_table
) s
where row_number < 3;
look at the order column (I use id to match your sample):
t=# with data as (select *,count(1) over (partition by sub_id order by id) from t)
select id,sub_id,datetime,resource from data where count <3;
id | sub_id | datetime | resource
----+--------+------------+----------
1 | 10 | 2009-03-04 | 399
3 | 10 | 2009-03-04 | 555
2 | 11 | 2009-03-04 | 244
5 | 11 | 2009-03-03 | 200
8 | 13 | 2009-01-01 | 750
10 | 13 | 2009-01-01 | 570
(6 rows)
Related
select * from rankings;
students | stu_id | card_id
----------+--------+---------
Charlie | 11 | 1
Shakira | 22 | 2
Selena | 33 | 3
Ross | 44 | 4
Chandler | 55 | 5
James | 66 | 6
Kylie | 77 | 7
Here is the table kindly tell me how we can apply the rank function in it with Postgresql?
I made a game, with level and scores saved into an sql table like this :
create table if not exists api.scores (
id serial primary key,
pseudo varchar(50),
level int,
score int,
created_at timestamptz default CURRENT_TIMESTAMP
);
I want to display the scores in the ui with the rank of each score, based on the score column, ordered by desc.
Here is a sample data :
id | pseudo | level | score | created_at
----+----------+-------+-------+-------------------------------
1 | test | 1 | 1 | 2020-05-01 11:25:20.446402+02
2 | test | 1 | 1 | 2020-05-01 11:28:11.04001+02
3 | szef | 1 | 115 | 2020-05-01 15:45:06.201135+02
4 | erg | 1 | 115 | 2020-05-01 15:55:19.621372+02
5 | zef | 1 | 115 | 2020-05-01 16:14:09.718861+02
6 | aa | 1 | 115 | 2020-05-01 16:16:49.369718+02
7 | zesf | 1 | 115 | 2020-05-01 16:17:42.504354+02
8 | zesf | 2 | 236 | 2020-05-01 16:18:07.070728+02
9 | zef | 1 | 115 | 2020-05-01 16:22:23.406013+02
10 | zefzef | 1 | 115 | 2020-05-01 16:23:49.720094+02
Here is what I want :
id | pseudo | level | score | created_at | rank
----+----------+-------+-------+-------------------------------+------
31 | zef | 7 | 730 | 2020-05-01 18:40:42.586224+02 | 1
50 | Cyprien | 5 | 588 | 2020-05-02 14:08:39.034112+02 | 2
49 | cyprien | 4 | 438 | 2020-05-01 23:35:13.440595+02 | 3
51 | Cyprien | 3 | 374 | 2020-05-02 14:13:41.071752+02 | 4
47 | cyprien | 3 | 337 | 2020-05-01 23:27:53.025475+02 | 5
45 | balek | 3 | 337 | 2020-05-01 19:57:39.888233+02 | 5
46 | cyprien | 3 | 337 | 2020-05-01 23:25:56.047495+02 | 5
48 | cyprien | 3 | 337 | 2020-05-01 23:28:54.190989+02 | 5
54 | Cyzekfj | 2 | 245 | 2020-05-02 14:14:34.830314+02 | 9
8 | zesf | 2 | 236 | 2020-05-01 16:18:07.070728+02 | 10
13 | zef | 1 | 197 | 2020-05-01 16:28:59.95383+02 | 11
14 | azd | 1 | 155 | 2020-05-01 17:53:30.372793+02 | 12
38 | balek | 1 | 155 | 2020-05-01 19:08:57.622195+02 | 12
I want to retreive the rank based on the full table whatever the result set.
I'm using the postgrest webserver.
How do I do that ?
You are describing window function rank():
select t.*, rank() over(order by score desc) rnk
from mytable t
order by score desc
I would like to create a count per user of number of records after the first time that x is not null for that user.
I have a table that is similar to the following:
id | user_id | completed_at | x
----+---------+--------------+---
1 | 1001 | 2017-06-01 | 1
20 | 1001 | 2017-06-01 | 2
21 | 1001 | 2017-06-02 | 4
22 | 1001 | 2017-06-03 |
24 | 1001 | 2017-06-03 |
25 | 1001 | 2017-06-04 |
23 | 1001 | 2017-06-04 |
12 | 1001 | 2017-06-06 |
13 | 1001 | 2017-06-07 |
14 | 1001 | 2017-06-08 |
2 | 1002 | 2017-06-02 | 3
27 | 1002 | 2017-06-02 | 7
15 | 1002 | 2017-06-09 |
3 | 1003 | 2017-06-03 |
4 | 1004 | 2017-06-04 |
5 | 1005 | 2017-06-05 |
33 | 1005 | 2017-06-20 | 8
34 | 1006 | 2017-07-10 | 9
6 | 1006 | 2017-10-06 |
7 | 1007 | 2017-10-07 |
8 | 1008 | 2017-10-08 |
9 | 1009 | 2017-10-09 |
10 | 1010 | 2017-10-10 |
16 | 1011 | 2017-06-01 |
11 | 1011 | 2017-07-01 | 5
17 | 1012 | 2017-06-02 |
26 | 1012 | 2017-07-02 | 6
18 | 1013 | 2017-06-03 |
19 | 1014 | 2017-06-04 |
31 | 1014 | 2017-06-24 |
32 | 1014 | 2017-06-24 |
30 | 1014 | 2017-06-24 |
29 | 1014 | 2017-06-24 |
28 | 1014 | 2017-06-24 |
The expected output would look like this:
+------+------------+---------------+
| user | first_x | records_after |
+------+------------+---------------+
| 1001 | 2017-06-01 | 9 |
| 1002 | 2017-06-02 | 2 |
| 1005 | 2017-06-20 | 0 |
| 1011 | 2017-07-01 | 0 |
| 1012 | 2017-07-02 | 0 |
+------+------------+---------------+
Using running count, and then conditional count for running count > 0
Sample
WITH flags AS (
SELECT
user_id,
completed_at,
sum(CASE WHEN x IS NULL THEN 0 ELSE 1 END) OVER (PARTITION BY user_id ORDER BY completed_at ROWS BETWEEN UNBOUNDED PRECEDING AND 0 FOLLOWING) AS flag
FROM users
),
completed AS (
SELECT DISTINCT ON (user_id)
user_id,
completed_at AS first_x
FROM flags
WHERE flag > 0
ORDER BY user_id, completed_at
)
SELECT DISTINCT
user_id AS user,
first_x,
count(flag) FILTER (WHERE flag>0) - 1 AS records_after
FROM flags
NATURAL JOIN completed
GROUP BY 1, 2
ORDER BY 1
I want to calculate average in Spotfire only when there are minimum 3 values. if there are no values or just 2 values the average should be blank
Raw data:
Product Age Average
1
2
3 10
4 12
5 13 11
6
7 18
8 19
9 20 19
10 21 20
The only way I could really do this is with 3 calculated columns. Insert these calculated columns in this order:
If(Min(If([Age] IS NULL,0,[Age])) over (LastPeriods(3,[Product]))<>0,1) as [BitFlag]
Avg([Age]) over (LastPeriods(3,[Product])) as [TempAvg]
If([BitFlag]=1,[TempAvg]) as [Average]
This will give you the following results. You can ignore / hide the two columns you don't care about.
RESULTS
+---------+-----+---------+------------------+------------------+
| Product | Age | BitFlag | TempAvg | Average |
+---------+-----+---------+------------------+------------------+
| 1 | | | | |
| 2 | | | | |
| 3 | 10 | | 10 | |
| 4 | 12 | | 11 | |
| 5 | 13 | 1 | 11.6666666666667 | 11.6666666666667 |
| 6 | | | 12.5 | |
| 7 | 18 | | 15.5 | |
| 8 | 19 | | 18.5 | |
| 9 | 20 | 1 | 19 | 19 |
| 10 | 21 | 1 | 20 | 20 |
| 11 | | | 20.5 | |
| 12 | 22 | | 21.5 | |
| 13 | 36 | | 29 | |
| 14 | | | 29 | |
| 15 | 11 | | 23.5 | |
| 16 | 23 | | 17 | |
| 17 | 14 | 1 | 16 | 16 |
+---------+-----+---------+------------------+------------------+
Now I need 5 formula for sum of each column, it works fine but I wish it can be simplified to one formula. Is it possible?
|----+----+----+-----+----|
| a | b | c | d | e |
|----+----+----+-----+----|
| 1 | 2 | 3 | 4 | 5 |
| 6 | 7 | 8 | 9 | 10 |
| 11 | 12 | 13 | 14 | 15 |
| 16 | 17 | 18 | 19 | 20 |
|----+----+----+-----+----|
| 34 | 38 | 42 | 160 | 50 |
|----+----+----+-----+----|
#+TBLFM: #>$5=vsum(#2$5..#-1$5)::#>$4=vsum(#2$1..#-1$4)::#>$3=vsum(#2$3..#-1$3)::#>$2=vsum(#2$2..#-1$2)::#>$1=vsum(#2$1..#-1$1)
This should work:
|----+----+----+----+----|
| a | b | c | d | e |
|----+----+----+----+----|
| 1 | 2 | 3 | 4 | 5 |
| 6 | 7 | 8 | 9 | 10 |
| 11 | 12 | 13 | 14 | 15 |
| 16 | 17 | 18 | 19 | 20 |
|----+----+----+----+----|
| 34 | 38 | 42 | 46 | 50 |
|----+----+----+----+----|
#+TBLFM: #>$1..#>$5=vsum(#2$0..#-1$0)
$0 on the RHS is the current column.