I have data of the following format as a result of a first query.
Now i need to add second query with a condition, which is hard for me and maybe someone can help me out with this one.
The condition is:
If the type for the customers row with the highest product_id is Y, then take all rows for given customer, if it is X then take non.
So I need to somehow select for each customer row with highest product_id, check if in that row type is Y, and then regarding on the result take all or non of the given customer data.
index customer product_id type
-----------------------------------------
1 1 51 X
2 1 42 Y
3 1 11 X
4 2 4 Y
5 2 2 Y
6 3 41 Y
7 3 22 Y
8 3 21 X
9 3 20 X
10 4 16 X
11 4 15 Y
12 4 14 Y
13 4 13 Y
14 4 12 Y
So in the example above I'd like to return rows: 4,5,6,7,8,9
Use FIRST_VALUE() window function:
SELECT [index], [customer], [product_id], [type]
FROM (
SELECT *, FIRST_VALUE([type]) OVER (PARTITION BY [customer] ORDER BY [product_id] DESC) [value]
FROM tablename
) t
WHERE [value] = 'Y'
See the demo.
Results:
> index | customer | product_id | type
> ----: | -------: | ---------: | :---
> 4 | 2 | 4 | Y
> 5 | 2 | 2 | Y
> 6 | 3 | 41 | Y
> 7 | 3 | 22 | Y
> 8 | 3 | 21 | X
> 9 | 3 | 20 | X
Related
I'd like to divide the data into separate groups (chunks) based on the value in the column. If the value increase above certain threshold, the value in the "group" should increase by 1.
This would be easy to achieve in MySQL, by doing CASE WHEN #val > 30 THEN #row_no + 1 ELSE #row_no END however I am using Amazon Redshift where this is not allowed.
Sample fiddle: http://sqlfiddle.com/#!15/00b3aa/6
Suggested output:
ID
Value
Group
1
11
1
2
11
1
3
22
1
4
11
1
5
35
2
6
11
2
7
11
2
8
11
2
9
66
3
10
11
3
A cumulative sum should do what you want:
SELECT *, sum((val>=30)::INTEGER) OVER (ORDER BY id BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW) FROM mydata ORDER BY id;
id | val | sum
----+-----+-----
1 | 11 | 0
2 | 11 | 0
3 | 22 | 0
4 | 11 | 0
5 | 35 | 1
6 | 11 | 1
7 | 11 | 1
8 | 11 | 1
9 | 66 | 2
10 | 11 | 2
Here's some sample data from my table:
day_number daily_users_count
1 1
3 1
6 1
7 1
9 2
10 2
I need all day_number values, from 1 to max(day_number), and I want daily_users_count to be zero if it isn't mentioned in this table.
It should look something like this:
day_number daily_users_count
1 1
2 0
3 1
4 0
5 0
6 1
7 1
8 0
9 2
10 2
I think a left join with a table which has a number column with all integers from 1 to max(day_number) would work, if I put a default value for daily_users_count as 0.
What I don't get is how to create such a table where all integers within a certain range are present. Any alternate solutions or any ways to do this would be much appreciated.
You can do it with a recursive CTE which will return all the day_numbers including the missing ones and then a LEFT join to the table:
with cte as (
select min(day_number) day_number from tablename
union all
select day_number + 1 from cte
where day_number < (select max(day_number) from tablename)
)
select c.day_number,
coalesce(t.daily_users_count, 0) daily_users_count
from cte c left join tablename t
on t.day_number = c.day_number
See the demo.
Results:
| day_number | daily_users_count |
| ---------- | ----------------- |
| 1 | 1 |
| 2 | 0 |
| 3 | 1 |
| 4 | 0 |
| 5 | 0 |
| 6 | 1 |
| 7 | 1 |
| 8 | 0 |
| 9 | 2 |
| 10 | 2 |
I have a table:
ID | rows | dimensions
---+------+-----------
1 | 1 | 15 x 20
2 | 3 | 2 x 10
3 | 5 | 23 x 33
3 | 7 | 15 x 23
4 | 2 | 12 x 32
And I want to have something like that:
ID | rows | dimensions
---+------+-----------
1 | 1 | 15 x 20
2 | 3 | 2 x 10
3a | 5 | 23 x 33
3b | 7 | 15 x 23
4 | 2 | 12 x 32
How can I find the multiple ID value to make it unique?
How can I update the parent table after?
Thanks for your help!
with stats as (
SELECT "ID",
"rows",
row_number() over (partition by "ID" order by rows) as rn,
count(*) over (partition by "ID") as cnt
FROM Table1
)
UPDATE Table1
SET "ID" = CASE WHEN s.cnt > 1 THEN s."ID" || '-' || s.rn
ELSE s."ID"
END
FROM stats s
WHERE S."ID" = Table1."ID"
AND S."rows" = Table1."rows"
I'm assuming you cant have two rows with same ID and same rows other wise you need to include "dimensions" on the WHERE too.
In this case the output is
I have a theoretical question, so I'm not interested in alternative solutions. Sorry.
Q: Is it possible to get the window running function values for all previous rows, except current?
For example:
with
t(i,x,y) as (
values
(1,1,1),(2,1,3),(3,1,2),
(4,2,4),(5,2,2),(6,2,8)
)
select
t.*,
sum(y) over (partition by x order by i) - y as sum,
max(y) over (partition by x order by i) as max,
count(*) filter (where y > 2) over (partition by x order by i) as cnt
from
t;
Actual result is
i | x | y | sum | max | cnt
---+---+---+-----+-----+-----
1 | 1 | 1 | 0 | 1 | 0
2 | 1 | 3 | 1 | 3 | 1
3 | 1 | 2 | 4 | 3 | 1
4 | 2 | 4 | 0 | 4 | 1
5 | 2 | 2 | 4 | 4 | 1
6 | 2 | 8 | 6 | 8 | 2
(6 rows)
I want to have max and cnt columns behavior like sum column, so, result should be:
i | x | y | sum | max | cnt
---+---+---+-----+-----+-----
1 | 1 | 1 | 0 | | 0
2 | 1 | 3 | 1 | 1 | 0
3 | 1 | 2 | 4 | 3 | 1
4 | 2 | 4 | 0 | | 0
5 | 2 | 2 | 4 | 4 | 1
6 | 2 | 8 | 6 | 4 | 1
(6 rows)
It can be achieved using simple subquery like
select t.*, lag(y,1) over (partition by x order by i) as yy from t
but is it possible using only window function syntax, without subqueries?
Yes, you can. This does the trick:
with
t(i,x,y) as (
values
(1,1,1),(2,1,3),(3,1,2),
(4,2,4),(5,2,2),(6,2,8)
)
select
t.*,
sum(y) over w as sum,
max(y) over w as max,
count(*) filter (where y > 2) over w as cnt
from t
window w as (partition by x order by i
rows between unbounded preceding and 1 preceding);
The frame_clause selects just those rows from the window frame that you are interested in.
Note that in the sum column you'll get null rather than 0 because of the frame clause: the first row in the frame has no row before it. You can coalesce() this away if needed.
SQLFiddle
I know the title doesn't explain my question very well (if someone can come up with a better title then please edit it). Here's what I want to do, say I have the following table:
id | a | b | c
------------------
1 | 3 | 3 | 3
2 | 20 | 40 | 30
3 | 40 | 30 | 10
4 | 30 | 10 | 15
5 | 10 | 15 | 6
6 | 15 | 6 | 20
This is slightly truncated version, I have a few more columns to sort by, but the principle behind the data & my question is the same.
What I would like is to get the data ordered in the following way:
The row with the highest value in col a
The row with the highest value in col b
The row with the highest value in col c
Followed by all remaining rows ordered by their value in col c
So, the result set would look like:
id | a | b | c
------------------
3 | 40 | 30 | 10
2 | 20 | 40 | 30
6 | 15 | 6 | 20
4 | 30 | 10 | 15
5 | 10 | 15 | 6
1 | 3 | 3 | 3
Doing a
SELECT id, a, b, c
FROM table
ORDER BY a DESC, b DESC, c DESC
Obviously gives me a ordered first, then b and finally c, so the following (which is not what I need):
id | a | b | c
------------------
3 | 40 | 30 | 10
4 | 30 | 10 | 15
2 | 20 | 40 | 30
6 | 15 | 6 | 20
5 | 10 | 15 | 6
1 | 3 | 3 | 3
I'm not familiar with the MySQL TSQL dialect but you would have to first SELECT the row with the highest 'A' value, perform a UNION ALL (i.e. no distinct via sorting) with the row with the highest 'B' value, perform a UNION ALL with the row with the highest 'C' value and then a UNION ALL with the remaining rows ordered by 'C' and excluding the 3 rows (by id) already selected.
I've just tested the following which appears to work (does involve 3 subqueries however):
SELECT id, a, b, c
FROM test
ORDER BY FIELD(a,(SELECT MAX(a) FROM test)) DESC,
FIELD(b,(SELECT MAX(b) FROM test)) DESC,
FIELD(c,(SELECT MAX(c) FROM test)) DESC,
c DESC