I'm very new to SQL and this one has me stumpted. Can you help me out with this query?
I have the following 2 tables:
TABLE 1: IssueTable
Id | RunId | Value
---
1 | 1 | 10
2 | 1 | 20
3 | 1 | 30
4 | 2 | 40
5 | 2 | 50
6 | 3 | 60
7 | 4 | 70
8 | 5 | 80
9 | 6 | 90
TABLE 2: RunTable
RunId | EnvironmentId
---
1 | 1
2 | 3
3 | 1
4 | 2
5 | 4
6 | 2
I need the IssueTable rows that represent the Max RunId grouped by the EnvironmentId in the RunTable. The result I would need from the tables is:
EXPECTED RESULT:
Id | RunId | Value | EnvironmentId
---
4 | 2 | 40 | 3
5 | 2 | 50 | 3
6 | 3 | 60 | 1
8 | 5 | 80 | 4
9 | 6 | 90 | 2
So only the rows with the most recent/highest RunId from the RunTable per EnvironmentId. For example, for the EnvironmentId of "1", I only want rows that contain a RunId of "3" because the most recent RunId on EnvironmentId "1" from the RunTable is "3". Likewise, the most recent run for EnvironementId "2" was RunId "6"
Use a subquery to get the max runid for each environmentid from the runtable. Join the obtained result to the issuetable and select the required columns.
select i.id, i.runid, i.value, r.environmentid
from (select environmentid, max(runid) maxrunid
from runtable
group by environmentid) r
join issuetable i on i.runid = r.maxrunid
order by i.runid, i.id
These days one can use the analytical functions like RANK, DENSE_RANK, ROW_NUMBER to generate some ranking of your records.
Window functions are part of the ANSI SQL:2003 standard.
And I've at least encountered them on TeraData, Oracle and SQL-Server.
select Id, RunId, Value, EnvironmentId
from (
select i.*, r.EnvironmentId,
dense_rank() over (partition by r.EnvironmentId order by r.RunId desc) as RN
from issuetable i
inner join runtable r on (i.RunId = r.RunId)
) Q
where RN = 1
order by Id;
The inner query would yield the following results :
Id RunId Value EnvironmentId RN
1 1 10 1 2
2 1 20 1 2
3 1 30 1 2
4 2 40 3 1
5 2 50 3 1
6 3 60 1 1
7 4 70 2 2
8 5 80 4 1
9 6 90 2 1
Related
I would like to know which row were moved to a bucket.
SELECT
width_bucket(s.score, sl.mins, sl.maxs, 9) as buckets,
COUNT(*)
FROM scores s
CROSS JOIN scores_limits sl
GROUP BY 1
ORDER BY 1;
My actual return:
buckets | count
---------+-------
1 | 182
2 | 37
3 | 46
4 | 15
5 | 29
7 | 18
8 | 22
10 | 11
| 20
What I expect to return:
SELECT buckets FROM buckets_table [...] WHERE scores.id = 1;
How can I get, for example, the column 'id' of table scores?
I believe you can include the id in an array with array_agg. If I recreate your case with
create table test (id serial, score int);
insert into test(score) values (10),(9),(5),(4),(10),(2),(5),(7),(8),(10);
The data is
id | score
----+-------
1 | 10
2 | 9
3 | 5
4 | 4
5 | 10
6 | 2
7 | 5
8 | 7
9 | 8
10 | 10
(10 rows)
Using the following and aggregating the id with array_agg
SELECT
width_bucket(score, 0, 10, 11) as buckets,
COUNT(*) nr_ids,
array_agg(id) agg_ids
FROM test s
GROUP BY 1
ORDER BY 1;
You get
buckets | nr_ids | agg_ids
---------+--------+----------
3 | 1 | {6}
5 | 1 | {4}
6 | 2 | {3,7}
8 | 1 | {8}
9 | 1 | {9}
10 | 1 | {2}
12 | 3 | {1,5,10}
I'm working with an Access database and have two tables:
ID_1
Number
Some other data
1
1
Data
2
2
Data
3
3
Data
4
4
Data
5
3
Data
6
1
Data
7
2
Data
8
3
Data
9
1
Data
10
1
Data
11
2
Data
12
3
Data
13
4
Data
14
1
Data
15
2
Data
16
3
Data
17
4
Data
18
3
Data
19
3
Data
ID_2
Number
Some other data
1
3
Data
2
1
Data
3
2
Data
4
3
Data
5
2
Data
As you see, both tables have duplicate data. I need a query that would select all the records in the first table that match each of the records in the second, they are related by Number field. It's also necessary that these records aren't repeated (that is, that the query doesn't repeat values when selecting). For the given example I should get this result:
ID
ID_1
Number
Some other data
1
3
3
Data
2
5
3
Data
3
8
3
Data
4
12
3
Data
5
16
3
Data
6
18
3
Data
7
19
3
Data
8
1
1
Data
9
6
1
Data
10
9
1
Data
11
10
1
Data
12
14
1
Data
13
2
2
Data
14
7
2
Data
15
11
2
Data
16
15
2
Data
I was thinking that maybe I could use Join, but I still don't know how; tried Where, but also didn't find a use for it. Could you please help me with that?
I don't see where you're generating your output ID field from - or where you're picking your Data field from so here's the best guess.
SELECT Table1.ID_1, Table1.Number, Table1.[Some other data]
FROM Table1
WHERE (Table1.Number In (SELECT Number From Table2))
ORDER BY Table1.Number, Table1.ID_1;
Looks like this:
MySql DB data structure
create table tbl1(ID_1 serial, Number int);
create table tbl2(ID_2 serial, Number int);
insert into tbl1(Number) values (1),(2),(3),(4),(3),(1),(2),(3),(1),(1),(2),(3),(4),(1),(2),(3),(4),(3),(3);
insert into tbl2(Number) values (3),(1),(2),(3),(2);
query (with s), needed to remove duplicates
the window function count(tbl1.Number) OVER(PARTITION BY Number) sorts the result for us by the count of matched numbers
the #rownum variable is needed to count rows
with s as (select distinct Number from tbl2),
f as (select ID_1,tbl1.Number from tbl1 left join s on
(tbl1.Number=s.Number) where s.Number is not null order by
count(tbl1.Number) OVER(PARTITION BY Number) desc)
select #rownum := #rownum + 1 AS ID,ID_1,Number from f, (SELECT #rownum := 0) r;
results
+------+------+--------+
| ID | ID_1 | Number |
+------+------+--------+
| 1 | 3 | 3 |
| 2 | 5 | 3 |
| 3 | 8 | 3 |
| 4 | 12 | 3 |
| 5 | 16 | 3 |
| 6 | 18 | 3 |
| 7 | 19 | 3 |
| 8 | 1 | 1 |
| 9 | 6 | 1 |
| 10 | 9 | 1 |
| 11 | 10 | 1 |
| 12 | 14 | 1 |
| 13 | 2 | 2 |
| 14 | 7 | 2 |
| 15 | 11 | 2 |
| 16 | 15 | 2 |
+------+------+--------+
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 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