I seek to find the maximum timestamp (ob.create_ts) for each group of marketid's (ob.marketid), joining tables obe (ob.orderbookid = obe.orderbookid) and market (ob.marketid = m.marketid). Although there are a number of solutions posted like this for a single table, when I join multiple tables, I get redundant results. Sample table and desired results below:
table: ob
orderbookid
marketid
create_ts
1
1
1664635255298
2
1
1664635255299
3
1
1664635255300
4
2
1664635255301
5
2
1664635255302
6
2
1664635255303
table: obe
orderbookentryid
orderbookid
entryname
1
1
'entry-1'
2
1
'entry-2'
3
1
'entry-3'
4
2
'entry-4'
5
2
'entry-5'
6
3
'entry-6'
7
3
'entry-7'
8
4
'entry-8'
9
5
'entry-9'
10
6
'entry-10'
table: m
marketid
marketname
1
'market-1'
2
'market-2'
desired results
ob.orderbookid
ob.marketid
obe.orderbookentryid
obe.entryname
m.marketname
3
1
6
'entry-6'
'market-1'
3
1
7
'entry-7'
'market-1'
6
2
10
'entry-10'
'market-2'
Use ROW_NUMBER() to get a properly filtered ob table. Then JOIN the other tables onto that!
WITH
ob_filtered AS (
SELECT
orderbookid,
marketid
FROM
(
SELECT
*,
ROW_NUMBER() OVER (
PARTITION BY
marketid
ORDER BY
create_ts DESC
) AS create_ts_rownumber
FROM
ob
) ob_with_rownumber
WHERE
create_ts_rownumber = 1
)
SELECT
ob_filtered.orderbookid,
ob_filtered.marketid,
obe.orderbookentryid,
obe.entryname,
m.marketname
FROM
ob_filtered
JOIN m
ON m.marketid = ob_filtered.marketid
JOIN obe
ON ob_filtered.orderbookid = obe.orderbookid
;
The first six balls mean first over, next six balls mean second over & so on than how to get average runs for each over.
input as
Ball no Runs
1 4
2 6
3 3
4 2
5 6
6 1
1 2
2 4
3 6
4 3
5 1
6 1
1 2
output should be:
Over no avg runs
1 3.66
2 2.83
As Gordon Linoff suggested, SQL table represents unordered sets, So you have to use an ordered column in your table. If you can use such a column you may use below query -
SELECT Over_no AVG(Runs) avg_runs
FROM (SELECT Ball_no, Runs, CEIL(ROW_NUMBER() OVER(ORDER BY ORDER_COLUMN, Ball_no) RN / 6) Over_no
FROM YOUR_TABLE)
GROUP BY Over_no;
I have managed to solve my problem with the following query:
SELECT ROWNUM OVER_NO, AVG_RUNS
FROM(
SELECT ROWNUM RN,
ROUND(AVG(RUNS)OVER(ORDER BY ROWNUM RANGE BETWEEN CURRENT ROW AND 5 FOLLOWING),2) AVG_RUNS
FROM TABLE_NAME
)
WHERE RN=1 OR RN=7;
I have two tables:
Report
ReportId CreatedDate
1 2018-01-12
2 2018-02-12
3 2018-03-12
ReportSpecialty
SpecialtyId ReportId IsPrimarySpecialty
1 1 1
2 2 1
3 3 1
1 2 0
1 3 0
I am trying to write a query that will retrieve me the last 10 reports that were published. However, I need to get 1 report from each specialty. Assume there are 100 specialties, I can pass in as an argument any number of specialties, 10, 20, 5, 2, etc...
I'm trying to figure out a way where if I send it all specialties, it will get me the last 10 reports posted based on the last date created, but it won't give me 2 articles from same specialty. If I send it 10 specialties, then I will get 1 of each. If I send it 5, then I'll get 2 of each. If I send it 3 then I'll get 4 of 1 and 3 of other two.
I may need to write multiple queries for this, I'm trying to see if there is a way to do this on the SQL side of things? If there isn't, then how would I break down to multiple queries to get the result I want?
What I have tried is this, however I get multiple reports with same specialties:
SELECT TOP 10 r.ReportId, rs.SpecialtyId, r.CreatedDate
FROM Report r
INNER JOIN ReportSpecialty rs ON r.ReportId = rs.ReportId AND rs.IsPrimarySpecialty = 1
GROUP BY rs.SpecialtyId, r.AceReportid, r.CreatedDate
ORDER BY r.CreatedDate DESC
with cte as (
SELECT R.ReportId, R.CreatedDate, RS.SpecialtyId,
ROW_NUMBER() OVER (PARTITION BY RS.SpecialtyId
ORDER BY R.CreatedDate DESC) as rn
FROM Report R
JOIN ReportSpecialty RS
ON R.ReportId = RS.ReportId
AND RS.IsPrimarySpecialty = 1
WHERE RS.SpecialtyId IN ( .... ids ... )
)
SELECT TOP 10 *
FROM cte
ORDER BY rn, CreatedDate DESC
row_number will create a id for each speciality, so if you pass 3 speciality you will get something like this.
rn speciality_id
1 1
1 2
1 3
2 1
2 2
2 3
3 1
3 2
3 3
I have the table below in an SQL database.
user rating
1 10
1 7
1 6
1 2
2 8
2 3
2 2
2 2
I would like to keep only the best two ratings by user to get:
user rating
1 10
1 7
2 8
2 3
What would be the SQL query to do that? I am not sure how to do it.
It will work
;with cte as
(select user,rating, row_number() over (partition by user order by rating desc) maxval
from yourtable)
select user,rating
from cte
where maxval in (1,2)
I have sets of consecutive integers, organized by type, in table1. All values are between 1 and 10, inclusive.
table1:
row_id set_id type min_value max_value
1 1 a 1 3
2 2 a 4 10
3 3 a 6 10
4 4 a 2 5
5 5 b 1 9
6 6 c 1 7
7 7 c 3 10
8 8 d 1 2
9 9 d 3 3
10 10 d 4 5
11 11 d 7 10
In table2, within each type, I want to assemble all possible maximal, non-overlapping sets (though gaps that cannot be filled by any sets of the correct type are okay). Desired output:
table2:
row_id type group_id set_id
1 a 1 1
2 a 1 2
3 a 2 1
4 a 2 3
5 a 3 3
6 a 3 4
7 b 4 5
8 c 5 6
9 c 6 7
10 d 7 8
11 d 7 9
12 d 7 10
13 d 7 11
My current idea is to use the fact that there is a limited number of possible values. Steps:
Find all sets in table1 containing value 1. Copy them into table2.
Find all sets in table1 containing value 2 and not already in table2.
Join the sets from (2) with table1 on type, set_id, and having min_value greater than the group's greatest max_value.
For the sets from (2) that did not join in (3), insert them into table2. These start new groups that may be extended later.
Repeat steps (2) through (4) for values 3 through 10.
I think this will work, but it has a lot of pain-in-the-butt steps, especially for (2)--finding the sets not in table2, and (4)--finding the sets that did not join.
Do you know a faster, more efficient method? My real data has millions of sets, thousands of types, and hundreds of values (though fortunately, as in the example, the values are bounded), so scalability is essential.
I'm using PLSQL Developer with Oracle 10g (not 11g as I stated before--thanks, IT department). Thanks!
For Oracle 10g you can't use recursive CTEs, but with a bit of work you can do something similar with the connect by syntax. First you need to generate a CTE or in-line view which has all the non-overlapping links, which you can do with:
select t1.type, t1.set_id, t1.min_value, t1.max_value,
t2.set_id as next_set_id, t2.min_value as next_min_value,
t2.max_value as next_max_value,
row_number() over (order by t1.type, t1.set_id, t2.set_id) as group_id
from table1 t1
left join table1 t2 on t2.type = t1.type
and t2.min_value > t1.max_value
where not exists (
select 1
from table1 t4
where t4.type = t1.type
and t4.min_value > t1.max_value
and t4.max_value < t2.min_value
)
order by t1.type, group_id, t1.set_id, t2.set_id;
This took a bit of experimentation and it's certainly possible I've missed or lost something about the rules in the process; but that gives you 12 pseudo-rows, and is in my previous answer this allows the two separate chains starting with a/1 to be followed while constraining the d values to a single chain:
TYPE SET_ID MIN_VALUE MAX_VALUE NEXT_SET_ID NEXT_MIN_VALUE NEXT_MAX_VALUE GROUP_ID
---- ------ ---------- ---------- ----------- -------------- -------------- --------
a 1 1 3 2 4 10 1
a 1 1 3 3 6 10 2
a 2 4 10 3
a 3 6 10 4
a 4 2 5 3 6 10 5
b 5 1 9 6
c 6 1 7 7
c 7 3 10 8
d 8 1 2 9 3 3 9
d 9 3 3 10 4 5 10
d 10 4 5 11 7 10 11
d 11 7 10 12
And that can be used as a CTE; querying that with a connect-by loop:
with t as (
... -- same as above query
)
select t1.type,
dense_rank() over (partition by null
order by connect_by_root group_id) as group_id,
t1.set_id
from t t1
connect by type = prior type
and set_id = prior next_set_id
start with not exists (
select 1 from table1 t2
where t2.type = t1.type
and t2.max_value < t1.min_value
)
and not exists (
select 1 from t t3
where t3.type = t1.type
and t3.next_max_value < t1.next_min_value
)
order by t1.type, group_id, t1.min_value;
The dense_rank() makes the group IDs contiguous; not sure if you actually need those at all, or if their sequence matters, so it's optional really. connect_by_root gives the group ID for the start of the chain, so although there were 12 rows and 12 group_id values in the initial query, they don't all appear in the final result.
The connection is via two prior values, type and the next set ID found in the initial query. That creates all the chains, but own its own would also include shorter chains - for d you'd see 8,9,10,11 but also 9,10,11 and 10,11, which you don't want as separate groups. Those are eliminated by the start with conditions, which could maybe be simplified.
That gives:
TYPE GROUP_ID SET_ID
---- -------- ------
a 1 1
a 1 2
a 2 1
a 2 3
a 3 4
a 3 3
b 4 5
c 5 6
c 6 7
d 7 8
d 7 9
d 7 10
d 7 11
SQL Fiddle demo.
If you can identify all the groups and their starting set_id then you can use a recursive approach and do this all in a single statement, rather than needing to populate a table iteratively. However you'd need to benchmark both approaches both for speed/efficiency and resource consumption - whether it will scale for your data volumes and within your system's available resources would need to be verified.
If I understand when you decide to start a new group you can identify them all at once with a query like:
with t as (
select t1.type, t1.set_id, t1.min_value, t1.max_value,
t2.set_id as next_set_id, t2.min_value as next_min_value,
t2.max_value as next_max_value
from table1 t1
left join table1 t2 on t2.type = t1.type and t2.min_value > t1.max_value
where not exists (
select 1
from table1 t3
where t3.type = t1.type
and t3.max_value < t1.min_value
)
)
select t.type, t.set_id, t.min_value, t.max_value,
t.next_set_id, t.next_min_value, t.next_max_value,
row_number() over (order by t.type, t.min_value, t.next_min_value) as grp_id
from t
where not exists (
select 1 from t t2
where t2.type = t.type
and t2.next_max_value < t.next_min_value
)
order by grp_id;
The tricky bit here is getting all three groups for a, specifically the two groups that start with set_id = 1, but only one group for d. The inner select (in the CTE) looks for sets that don't have a lower non-overlapping range via the not exists clause, and outer-joins to the same table to get the next set(s) that don't overlap, which gives you two groups that start with set_id = 1, but also four that start with set_id = 9. The outer select then ignores everything but the lowest non-overlapping with a second not exists clause - but doesn't have to hit the real table again.
So that gives you:
TYPE SET_ID MIN_VALUE MAX_VALUE NEXT_SET_ID NEXT_MIN_VALUE NEXT_MAX_VALUE GRP_ID
---- ------ ---------- ---------- ----------- -------------- -------------- ------
a 1 1 3 2 4 10 1
a 1 1 3 3 6 10 2
a 4 2 5 3 6 10 3
b 5 1 9 4
c 6 1 7 5
c 7 3 10 6
d 8 1 2 9 3 3 7
You can then use that as the anchor member in a recursive subquery factoring clause:
with t as (
...
),
r (type, set_id, min_value, max_value,
next_set_id, next_min_value, next_max_value, grp_id) as (
select t.type, t.set_id, t.min_value, t.max_value,
t.next_set_id, t.next_min_value, t.next_max_value,
row_number() over (order by t.type, t.min_value, t.next_min_value)
from t
where not exists (
select 1 from t t2
where t2.type = t.type
and t2.next_max_value < t.next_min_value
)
...
If you left the r CTE with that and just did sleect * from r you'd get the same seven groups.
The recursive member then uses the next set_id and its range from that query as the next member of each group, and repeats the outer join/not-exists look up to find the next set(s) again; stopping when there is no next non-overlapping set:
...
union all
select r.type, r.next_set_id, r.next_min_value, r.next_max_value,
t.set_id, t.min_value, t.max_value, r.grp_id
from r
left join table1 t
on t.type = r.type
and t.min_value > r.next_max_value
and not exists (
select 1 from table1 t2
where t2.type = r.type
and t2.min_value > r.next_max_value
and t2.max_value < t.min_value
)
where r.next_set_id is not null -- to stop looking when you reach a leaf node
)
...
Finally you have a query based on the recursive CTE to get the columns you want and to specify the order:
...
select r.type, r.grp_id, r.set_id
from r
order by r.type, r.grp_id, r.min_value;
Which gets:
TYPE GRP_ID SET_ID
---- ---------- ----------
a 1 1
a 1 2
a 2 1
a 2 3
a 3 4
a 3 3
b 4 5
c 5 6
c 6 7
d 7 8
d 7 9
d 7 10
d 7 11
SQL Fiddle demo.
If you wanted to you could show the min/max values for each set, and could track and show the min/max value for each group. I've just show then columns from the question though.