I have a result table
id | name | wins
----+-------------------
57 | Paul | 10
64 | Sven | 9
62 | Peter | 9
59 | Marina | 8
58 | Carlos | 4
60 | Pamela | 3
61 | Marcus | 2
63 | Hank | 1
Where I want to pair every nth entry with every (n+1)th entry, such that the resulting table looks like that:
id | name | id | name
----+-------------------
57 | Paul | 64 | Sven
62 | Peter | 59 | Marina
58 | Carlos | 60 | Pamela
61 | Marcus | 63 | Hank
Which SQL statement would achieve that?
;WITH cte AS (
SELECT *,ROW_NUMBER() OVER (ORDER BY Wins DESC) as RowNum
FROM
#Table
)
SELECT *
FROM
cte c1
LEFT JOIN cte c2
ON c1.RowNum + 1 = c2.RowNum
WHERE
c1.RowNum % 2 <> 0
Generate a ROW_NUMBER to use, seeing you have a third Column replace (SELECT NULL) in the Order by statement with that third column.
Then select all rows that are Odd Row numbers (remainder of RowNum divided by 2 <> 0 ) and self join back to itself with RowNum + 1. If you have an odd number of Rows you might consider using LEFT JOIN so you don't drop off the 1 row that won't have a match.
Related
So I've two tables 'AllBowlRecords' and one 'AggregateBowlRecords'
AllBowlRecords :-
plr_fullnm|Wkts|Runs
---------------------
Bumrah | 4 | 23
Bumrah | 2 | 7
Bumrah | 1 | 51
Bumrah | 4 | 39
Jason | 3 | 48
Jason | 3 | 29
Jason | 3 | 70
So all I want is to update AggregateBowlRecords based on AllBowlRecords where Wkts is MAX, but if there's multiple occurrences of MAX Wkts value, then whichever corresponds minimum runs should be selected. And AggregateBowlRecords should look like this:
Bumrah | 4 | 23
Jason | 3 | 29
What are the possible solutions?
You can return the results you want using a query with row_number():
select plr_fullnm, Wkts, Runs
from (select abr.*,
row_number() over (partition by plr_fullnm order by wkts desc, runs) as seqnum
from AllBowlRecords abr
) abr
where seqnum = 1;
Here is a table
ID | Player | Position | Points
1 | Ryan | QB | 75
2 | Matt | RB | 80
3 | Mike | WR | 66
4 | Jay | QB | 71
6 | Alvin | TE | 73
7 | Adrian | TE | 84
8 | Hill | WR | 71
9 | Charles| RB | 53
10 | Bell | WR | 87
11 | Rob | TE | 49
12 | Alex | RB | 92
13 | Drew | QB | 84
14 | Mack | TE | 59
15 | Nick | WR | 33
I want to report all the players in the position of the player having highest points and top 2 players of the other positions. In this example, "Alex" has the highest points and is a "RB". So I want to report all players from "RB" and top 2 from "QB", "TE", "WR" and order by points with in each group. I'm using sqlite3. I can do this programmatically using python and sqlite3 but i was wondering if this could be done only using sql
ID | Player | Position | Points
12 | Alex | RB | 92
2 | Matt | RB | 80
9 | Charles| RB | 53
13 | Drew | QB | 84
1 | Ryan | QB | 75
10 | Bell | WR | 87
8 | Hill | WR | 71
7 | Adrian | TE | 84
6 | Alvin | TE | 73
Thanks for your help
This is tricky in "traditional" SQLite. I would recommend union all:
with top1 as (
select t.*
from t
order by points desc
limit 1
)
select t.*
from t
where t.position = (select t1.position from top1 t1)
union all
select t.*
from t
where t.position <> (select t1.position from top1 t1) and
(select count(*)
from t t2
where t2.position = t.position and
t2.points >= t.points
) <= 2;
This assumes that the points values are unique. Ties are much harder to deal with in SQLite.
I might recommend that you consider upgrading to SQLite version 3.25.0 or use another database. Such a query would be much simpler using ISO/ANSI standard window functions.
With window functions, it would look like:
select t.*
from (select t.*,
row_number() over (partition by position order by points desc) as seqnum,
first_value(position) over (order by points desc) as first_position
from t
) t
where seqnum <= 2 or position = first_position
I have SQL results that I need to break into item ranges and the count distributed evenly across a number of tasks. What is a good way to do this?
My data looks like this.
+------+-------+----------+
| Item | Count | ItmGroup |
+------+-------+----------+
| 1A | 100 | 1 |
| 1B | 25 | 1 |
| 1C | 2 | 1 |
| 1D | 6 | 1 |
| 2A | 88 | 2 |
| 2B | 10 | 2 |
| 2C | 122 | 2 |
| 2D | 12 | 2 |
| 3A | 4 | 3 |
| 3B | 103 | 3 |
| 3C | 1 | 3 |
| 3D | 22 | 3 |
| 4A | 55 | 4 |
| 4B | 42 | 4 |
| 4C | 100 | 4 |
| 4D | 1 | 4 |
+------+-------+----------+
Item = the item code.
Count = this context it is determining the popularity of the item. This can be used to RANK items if need be.
ItmGroup - this is a parent value for the Itm column. Item is contained in a Group.
What differentiates this from other similar questions I'veviewed is that the ranges I need to determine cannot be taken out of the order they show in this table. We can do Item Range from A1 to B3, in other words, they can cross over ItmGroups, but they must remain in alphanumeric order by Item.
The expected result would be item ranges that evenly distribute the total count.
+------+-------+----------+
| FrItem | ToItem | TotCount|
+------+-------+----------+
| 1A | 2D | 134 |
| 3A | 3D | 130 |
(etc)
Provided you've happy with a rough estimate, this will split the data in to two groups.
The first group will always have as many records as possible, but no more than half of the total count (and group 2 will have the rest).
WITH
cumulative AS
(
SELECT
*,
SUM([Count]) OVER (ORDER BY Item) AS cumulativeCount,
SUM([Count]) OVER () AS totalCount
FROM
yourData
)
SELECT
MIN(item) AS frItem,
MAX(item) AS toItem,
SUM([Count]) AS TotCount
FROM
cumulative
GROUP BY
CASE WHEN cumulativeCount <= totalCount / 2 THEN 0 ELSE 1 END
ORDER BY
CASE WHEN cumulativeCount <= totalCount / 2 THEN 0 ELSE 1 END
To split the data in to 5 portions, it's similar...
GROUP BY
CASE WHEN cumulativeCount <= totalCount * 1/5 THEN 0
WHEN cumulativeCount <= totalCount * 2/5 THEN 1
WHEN cumulativeCount <= totalCount * 3/5 THEN 2
WHEN cumulativeCount <= totalCount * 4/5 THEN 3
ELSE 4 END
Depending on your data this isn't necessarily ideal
Item | Count GroupAsDefinedAbove IdealGroup
------+-------
1A | 4 1 1
2A | 5 2 1
3A | 8 2 2
If you want something that can get the two groups as close in size as possible, that's a lot more complex.
Same as the accepted answer, except declaring a batch number and an addition to the select statement in the WITH cumulativeCte to prevent a remainder.
DECLARE #BatchCount NUMERIC(4,2) = 5.00;
WITH
cumulativeCte AS
(
SELECT
*,
SUM(r.[Count]) OVER (ORDER BY Item) AS cumulativeCount,
SUM(r.[Count]) OVER () AS totalCount
,CEILING(SUM(r.[Count]) OVER (ORDER BY IM.MMITNO ASC) / (SUM(r.[Count]) OVER () / #BatchCount)) AS BatchNo
FROM
records r
)
SELECT
MIN(c.Item) AS frItem,
MAX(c.Item) AS toItem,
SUM(c.[Count]) AS TotCount,
c.BatchNo
FROM
cumulativeCte c
GROUP BY
c.BatchNo
ORDER BY
c.BatchNo
I am trying to select multiple columns from a table, but I want to select top certain number of records based on one column. I tried this :
select roll_no ,marks as Percentage
from database
where marks in (select top (3) *
from database
where subject = ''
order by marks desc) order by percentage desc
and I am getting the error:
Only one expression can be specified in the select list when the
sub-query is not introduced with EXISTS or more than specified number
of records.
I also tried :
select roll_no ,marks as Percentage
from database
where marks in (select top (3) marks
from database
where subject = ''
order by marks desc) order by percentage desc
which returns the right result for some subjects but for others..it is displaying top marks from other subjects as well.
eg :
+---------+-------+
| roll_no | marks |
+---------+-------+
|10003 | 87 |
|10006 | 72 |
|10003 | 72 |
|10002 | 67 |
|10004 | 67 |
+---------+-------+
How to frame the query correctly?
sample data :
+---------+-------+---------+
| roll_no | marks |subject |
+---------+-------+---------+
|10001 | 45 | Maths |
|10001 | 72 | Science |
|10001 | 64 | English |
|10002 | 52 | Maths |
|10002 | 35 | Science |
|10002 | 75 | English |
|10003 | 52 | Maths |
|10003 | 35 | Science |
|10003 | 75 | English |
|10004 | 52 | Maths |
|10004 | 35 | Science |
|10004 | 75 | English |
+---------+-------+---------+
If I'm right and you are looking for the best 3 marks for each subject, then you can get it with the following:
DECLARE #SelectedSubject VARCHAR(50) = 'Maths'
;WITH FilteredSubjectMarks AS
(
SELECT
D.Subject,
D.Roll_no,
D.Marks,
MarksRanking = DENSE_RANK() OVER (ORDER BY D.Marks DESC)
FROM
[Database] AS D
WHERE
D.Subject = #SelectedSubject
)
SELECT
F.*
FROM
FilteredSubjectMarks AS F
WHERE
F.MarksRanking <= 3
You can use window functions to rank your marks column (specifically dense_rank, which allows duplicate rankings whilst retaining sequential numbering) and then return all rows with a rank of 3 or less:
declare #t table(roll_no int identity(1,1),marks int);
insert into #t(marks) values(2),(4),(5),(8),(6),(1),(3),(2),(1),(8);
with t as
(
select roll_no
,marks
,dense_rank() over (order by marks desc) as r
from #t
)
select *
from t
where r <= 3;
Output:
+---------+-------+---+
| roll_no | marks | r |
+---------+-------+---+
| 4 | 8 | 1 |
| 10 | 6 | 1 |
| 5 | 6 | 2 |
| 3 | 5 | 3 |
+---------+-------+---+
Hey all I have the following tables that need in order to get data from one that matches the other and have it from highest to lowest depending on the int of TempVersion.
UPDATE
net_Users
SET
net_Users.DefaultId = b.TId
FROM
(SELECT
TOP 1 IndivId,
TId
FROM
UTeams
WHERE
UTeams.[Active] = 1
ORDER BY
TempVersion DESC
) AS b
WHERE
net_Users.IndivId = b.IndivId
In the above I am trying to order from the highest TempVersion to the lowest.
The query above seems to just update 1 of those records with the TempVersion and stop there. I am needing it to loop to find all associated users with the same IndivId matching.
Anyone able to help me out with this?
sample data
net_Users:
name | DefaultId | IndivId | etc...
--------+-----------+---------+-------
Bob | | 87 | etc...
Jan | | 231 | etc...
Luke | | 8 | etc...
UTeams:
IndivId | TempVersion | etc...
--------+-------------+-------
8 | 44 | etc...
17 | 18 | etc...
8 | 51 | etc...
8 | 2 | etc...
7 | 22 | etc...
8 | 125 | etc...
87 | 10 | etc...
14 | 88 | etc...
8 | 5 | etc...
15 | 54 | etc...
65 | 11 | etc...
87 | 15 | etc...
39 | 104 | etc...
And the output I would be needing is (going to choose IndivId 8):
In net_users:
Name | DefaultId | IndivId | etc...
-----+-----------+---------+-------
Luke | 125 | 8 | etc...
Luke | 51 | 8 | etc...
Luke | 44 | 8 | etc...
Luke | 5 | 8 | etc...
Luke | 2 | 8 | etc...
I think this is what you were trying to do:
update net_Users
set net_Users.DefaultId = coalesce((
select top 1 TId
from UTeams
where UTeams.[Active] = 1
and net_Users.IndivId = UTeams.IndivId
order by u.TempVersion desc
)
,net_Users.DefaultId
)
another way using cross apply()
update n
set DefaultId = coalesce(x.Tid,n.DefaultId)
from net_Users as n
cross apply (
select top 1 TId
from UTeams as u
where u.[Active] = 1
and n.IndivId = u.IndivId
order by u.TempVersion desc
) as x
another way to do that with a common table expression and row_number()
with cte as (
select
n.IndivId
, n.DefaultId
, u.Tid
, rn = row_number() over (
partition by n.IndivId
order by TempVersion desc
)
from net_users as n
inner join UTeams as u
on n.IndivId = u.IndivId
where u.[Active]=1
)
update cte
set DefaultId = Tid
where rn = 1