Is it possible to solve this situation by sql query in ORACLE?
I have a table like this:
TYPE UNIT
A 230
B 225
C 60
D 45
E 5
F 2
I need to separate units to the three(variable) 'same'(equally sized) intervals and foreach figure out the count? It means something like this:
0 - 77 -> 4
78 - 154 -> 0
155 - 230 -> 2
You can use the maximum value and a connect-by query to generate the upper and lower values for each range:
select ceil((level - 1) * int) as int_from,
floor(level * int) - 1 as int_to
from (select round(max(unit) / 3) as int from t42)
connect by level <= 3;
INT_FROM INT_TO
---------- ----------
0 76
77 153
154 230
And then do a left outer join to your original table to do the count for each range, so you get the zero value for the middle range:
with intervals as (
select ceil((level - 1) * int) as int_from,
floor(level * int) - 1 as int_to
from (select round(max(unit) / 3) as int from t42)
connect by level <= 3
)
select i.int_from || '-' || i.int_to as range,
count(t.unit)
from intervals i
left join t42 t
on t.unit between i.int_from and i.int_to
group by i.int_from, i.int_to
order by i.int_from;
RANGE COUNT(T.UNIT)
---------- -------------
0-76 4
77-153 0
154-230 2
Yes, this can be done in Oracle. The hard part is the definition of the bounds. You can use the maximum value and some arithmetic on a sequence with values of 1, 2, and 3.
After that, the rest is just a cross join and aggregation:
with bounds as (
select (case when n = 1 then 0
when n = 2 then trunc(maxu / 3)
else trunc(2 * maxu / 3)
end) as lowerbound,
(case when n = 1 then trunc(maxu / 3)
when n = 2 then trunc(2*maxu / 3)
else maxu
end) as upperbound
from (select 1 as n from dual union all select 2 from dual union all select 3 from dual
) n cross join
(select max(unit) as maxu from atable t)
)
select b.lowerbound || '-' || b.upperbound,
sum(case when units between b.lowerbound and b.upperbound then 1 else 0 end)
from atable t cross join
bounds b
group by b.lowerbound || '-' || b.upperbound;
Related
Problem statement is to calculate median from a table that has two columns. One specifying a number and the other column specifying the frequency of the number.
For e.g.
Table "Numbers":
Num
Freq
1
3
2
3
This median needs to be found for the flattened array with values:
1,1,1,2,2,2
Query:
with ct1 as
(select num,frequency, sum(frequency) over(order by num) as sf from numbers o)
select case when count(num) over(order by num) = 1 then num
when count(num) over (order by num) > 1 then sum(num)/2 end median
from ct1 b where sf <= (select max(sf)/2 from ct1) or (sf-frequency) <= (select max(sf)/2 from ct1)
Is it not possible to use count(num) over(order by num) as the condition in the case statement?
Find the relevant row / 2 rows based of the accumulated frequencies, and take the average of num.
The example and Fiddle will also show you the
computations leading to the result.
If you already know that num is unique, rowid can be removed from the ORDER BY clauses
with
t1 as
(
select t.*
,nvl(sum(freq) over (order by num,rowid rows between unbounded preceding and 1 preceding),0) as freq_acc_sum_1
,sum(freq) over (order by num, rowid) as freq_acc_sum_2
,sum(freq) over () as freq_sum
from t
)
select t1.*
,case
when freq_sum/2 between freq_acc_sum_1 and freq_acc_sum_2
then 'V'
end as relevant_record
from t1
order by num, rowid
Fiddle
Example:
ID
NUM
FREQ
FREQ_ACC_SUM_1
FREQ_ACC_SUM_2
FREQ_SUM
RELEVANT_RECORD
7
8
1
0
1
18
5
10
1
1
2
18
1
29
3
2
5
18
6
31
1
5
6
18
3
33
2
6
8
18
4
41
1
8
9
18
V
9
49
2
9
11
18
V
2
52
1
11
12
18
8
56
3
12
15
18
10
92
3
15
18
18
MEDIAN
45
Fiddle for 1M records
You can find the one (or two) middle value(s) and then average:
SELECT AVG(num) AS median
FROM (
SELECT num,
freq,
SUM(freq) OVER (ORDER BY num) AS cum_freq,
(SUM(freq) OVER () + 1)/2 AS median_freq
FROM table_name
)
WHERE cum_freq - freq < median_freq
AND median_freq < cum_freq + 1
Or, expand the values using a LATERAL join to a hierarchical query and then use the MEDIAN function:
SELECT MEDIAN(num) AS median
FROM table_name t
CROSS JOIN LATERAL (
SELECT LEVEL
FROM DUAL
WHERE freq > 0
CONNECT BY LEVEL <= freq
)
Which, for the sample data:
CREATE TABLE table_name (Num, Freq) AS
SELECT 1, 3 FROM DUAL UNION ALL
SELECT 2, 3 FROM DUAL;
Outputs:
MEDIAN
1.5
(Note: For your sample data, there are 6 items, an even number, so the MEDIAN will be half way between the value of 3rd and 4rd items; so half way between 1 and 2 = 1.5.)
db<>fiddle here
I'm trying to select a record by ID, they all have the same base value, but different multipliers.
so i want the base value multiplied by whatever comes next like given image shows
Try this:
SELECT
a.*,
a.value * ( 1 + SUM(a.multiplier) OVER(
PARTITION BY id
) / 100 ) desired_column
FROM
aux a;
Output
ID VALUE MULTIPLIER DESIRED_COLUMN
1 120 2 126
1 120 3 126
2 110 4 123.2
2 110 8 123.2
If you want just one row per id, then go with this:
SELECT
a.id,
a.value * ( 1 + SUM(a.multiplier) / 100 ) desired_column
FROM
aux a
GROUP BY
a.id,
a.value;
Output
ID DESIRED_COLUMN
1 126
2 123.2
Are you looking for arithmetic?
select t.*, (value * (1.0 + multiplier / 100.0)) as calculated_value
from t;
I am trying to break up a running (ordered) sum into groups of a max value. When I implement the following example logic...
IF OBJECT_ID(N'tempdb..#t') IS NOT NULL DROP TABLE #t
SELECT TOP (ABS(CHECKSUM(NewId())) % 1000) ROW_NUMBER() OVER (ORDER BY name) AS ID,
LEFT(CAST(NEWID() AS NVARCHAR(100)),ABS(CHECKSUM(NewId())) % 30) AS Description
INTO #t
FROM sys.objects
DECLARE #maxGroupSize INT
SET #maxGroupSize = 100
;WITH t AS (
SELECT
*,
LEN(Description) AS DescriptionLength,
SUM(LEN(Description)) OVER (/*PARTITION BY N/A */ ORDER BY ID) AS [RunningLength],
SUM(LEN(Description)) OVER (/*PARTITION BY N/A */ ORDER BY ID)/#maxGroupSize AS GroupID
FROM #t
)
SELECT *, SUM(DescriptionLength) OVER (PARTITION BY GroupID) AS SumOfGroup
FROM t
ORDER BY GroupID, ID
I am getting groups that are larger than the maximum group size (length) of 100.
A recusive common table expression (rcte) would be one way to resolve this.
Sample data
Limited set of fixed sample data.
create table data
(
id int,
description nvarchar(20)
);
insert into data (id, description) values
( 1, 'qmlsdkjfqmsldk'),
( 2, 'mldskjf'),
( 3, 'qmsdlfkqjsdm'),
( 4, 'fmqlsdkfq'),
( 5, 'qdsfqsdfqq'),
( 6, 'mds'),
( 7, 'qmsldfkqsjdmfqlkj'),
( 8, 'qdmsl'),
( 9, 'mqlskfjqmlkd'),
(10, 'qsdqfdddffd');
Solution
For every recursion step evaluate (r.group_running_length + len(d.description) <= #group_max_length) if the previous group must be extended or a new group must be started in a case expression.
Set group target size to 40 to better fit the sample data.
declare #group_max_length int = 40;
with rcte as
(
select d.id,
d.description,
len(d.description) as description_length,
len(d.description) as running_length,
1 as group_id,
len(d.description) as group_running_length
from data d
where d.id = 1
union all
select d.id,
d.description,
len(d.description),
r.running_length + len(d.description),
case
when r.group_running_length + len(d.description) <= #group_max_length
then r.group_id
else r.group_id + 1
end,
case
when r.group_running_length + len(d.description) <= #group_max_length
then r.group_running_length + len(d.description)
else len(d.description)
end
from rcte r
join data d
on d.id = r.id + 1
)
select r.id,
r.description,
r.description_length,
r.running_length,
r.group_id,
r.group_running_length,
gs.group_sum
from rcte r
cross apply ( select max(r2.group_running_length) as group_sum
from rcte r2
where r2.group_id = r.group_id ) gs -- group sum
order by r.id;
Result
Contains both the running group length as well as the group sum for every row.
id description description_length running_length group_id group_running_length group_sum
-- ---------------- ------------------ -------------- -------- -------------------- ---------
1 qmlsdkjfqmsldk 14 14 1 14 33
2 mldskjf 7 21 1 21 33
3 qmsdlfkqjsdm 12 33 1 33 33
4 fmqlsdkfq 9 42 2 9 39
5 qdsfqsdfqq 10 52 2 19 39
6 mds 3 55 2 22 39
7 qmsldfkqsjdmfqlkj 17 72 2 39 39
8 qdmsl 5 77 3 5 28
9 mqlskfjqmlkd 12 89 3 17 28
10 qsdqfdddffd 11 100 3 28 28
Fiddle to see things in action (includes random data version).
I have a table for subjects as follows:
id Subject Grade Ext
100 Math 6 +
100 Science 4 -
100 Hist 3
100 Geo 2 +
100 CompSi 1
I am expecting output per student in a class(id = 100) as follows:
Grade Ext StudentGrade
6 + 1
6 0
6 - 0
5 + 0
5 0
5 - 0
4 + 0
4 0
4 - 1
3 + 0
3 1
3 - 0
2 + 1
2 0
2 - 0
1 + 0
1 1
1 - 0
I would want this done on oracle/sql rather than UI. Any inputs please.
You should generate rows first, before join them with your table like below. I use the with clause here to generate the 18 rows in your sample.
with rws (grade, ext) as (
select ceil(level/3), decode(mod(level, 3), 0, '+', 1, '-', null)
from dual
connect by level <= 3 * 6
)
select r.grade, r.ext, nvl2(t.Ext, 1, 0) studentGrade
from rws r
left join your_table t
on t.Grade = r.Grade and decode(t.Ext, r.Ext, 1, 0) = 1
order by 1 desc, decode(r.ext, null, 2, '-', 3, '+', 1)
You could do something like this. In the WITH clause I generate two small "helper" tables (really, inline views) for grades from 1 to 6 and for "extensions" of +, null and -. In the "extensions" view I also create an "ordering" column to use in ordering the final output (if you are wondering why I included that).
Also in the WITH clause I included sample data - you will have to remove that and instead use your actual table name in the main query.
The idea is to cross-join "grades" and "extensions", and left-outer-join the result to your input data. Count the grades from the input data, grouped by grade and extension, and after filtering the desired id. The decode thing in the join condition is needed because for extension we want to treat null as equal to null - something that decode does nicely.
with
sample_inputs (id, subject, grade, ext) as (
select 100, 'Math' , 6, '+' from dual union all
select 100, 'Science', 4, '-' from dual union all
select 100, 'Hist' , 3, null from dual union all
select 100, 'Geo' , 2, '+' from dual union all
select 100, 'CompSi' , 1, null from dual
)
, g (grade) as (select level from dual connect by level <= 6)
, e (ord, ext) as (
select 1, '+' from dual union all
select 2, null from dual union all
select 3, '-' from dual
)
select g.grade, e.ext, count(t.grade) as studentgrade
from g cross join e left outer join sample_inputs t
on t.grade = g.grade and decode(t.ext, e.ext, 0) = 0
and t.id = 100 -- change this as needed!
group by g.grade, e.ext, e.ord
order by g.grade desc, e.ord
;
OUTPUT:
GRADE EXT STUDENTGRADE
----- --- ------------
6 + 1
6 0
6 - 0
5 + 0
5 0
5 - 0
4 + 0
4 0
4 - 1
3 + 0
3 1
3 - 0
2 + 1
2 0
2 - 0
1 + 0
1 1
1 - 0
It looks like you want sparse data to be filled in as part of joining students and subjects.
Since Oracle 10g the correct way to do this has been with a "partition outer join".
The documentation has examples.
https://docs.oracle.com/en/database/oracle/oracle-database/21/sqlrf/SELECT.html#GUID-CFA006CA-6FF1-4972-821E-6996142A51C6
I have the following data:
ID Days
----------------------- --------
1 5
1 10
1 15
2 5
2 13
2 15
I am trying to build out a range of numbers based on the days while grouping by their ID.
For ID Group 1: The range would start at 5 and end at 9. The next range would be 10-14, and then the final range would be 15-9999
For ID Group 2: The range would start at 5 and end at 12. The next range would be 13-14, and then the final range would be 15-9999
The resulting table would look something like this:
RangeStart RangeEnd RangeText ID
----------- ----------- --------- ----
5 9 5 - 9 1
10 14 10 - 14 1
15 9999 15 - 9999 1
5 12 5 - 12 2
13 14 13 - 14 2
15 9999 15 - 9999 2
I have attempted to use a CTE which works but only when I am not grouping by ID's.
Declare #RangeTable Table
(
ID Int,
RangeStart INT,
RangeEnd INT,
RangeText Varchar(50),
);with CTE as (
SELECT temp.Days,
rn = ROW_NUMBER() over(order by temp.Days asc),
temp.ID
FROM #TableWithDays temp)
INSERT #RangeTable
SELECT
ID= d1.ID,
RangeStart= ISNULL(d1.Days, 0),
RangeEnd = ISNULL(d2.Days- 1, 9999),
RangeText =
CASE WHEN (d1.Days = d2.Days - 1)
THEN CAST(d1.Days AS VARCHAR(100))
ELSE
ISNULL(CAST(d1.Days AS VARCHAR(100)),'0') + ISNULL(' - '+
CAST(d2.Days - 1 AS VARCHAR(100)),' - 9999')END
FROM
CTE d1 LEFT JOIN
CTE d2
ON d1.rn = d2.rn - 1
You can use a recursive CTE. This would be simpler with lead(), but that is not available. So:
with t as (
select t.*, t2.days as next_days
from #TableWithDays t outer apply
(select top (1) t2.*
from #TableWithDays t2
where t2.id = t.id and t2.days > t.days
order by t2.days desc
) t2
),
cte as (
select t.id, t.days, t.next_days
from t
union all
select cte.id, cte.days + 1, cte.next_days
from cte
where cte.days < cte.next_days or
(cte.days < 9999 and cte.next_days is null)
)
select *
from cte
with option (maxrecursion 0);