I have SQL server data Table, like this:
ID
SYMPTOM1
SYMPTOM2
1
A
B
1
C
D
2
E
F
3
A
C
3
D
E
I'd like to obtain this:
ID
SYMPTOM1
SYMPTOM2
SYMPTOM3
SYMPTOM4
1
A
B
C
D
2
E
F
3
A
C
D
E
That should be an "easy" pivot, but I can't figure it out.
How could a SQL query be written?
*EDIT
Excuse me, I have neglected an important detail. The number of rows in the table is very large, some 500.000 so the IDs are very large.
You could do it as a self join - use row number to have another column that is either 1 or 2 (depending on how many times ID appeared), 1 should always appear, 2 sometimes appears, so left joining those rows with 2 onto those rows with 1 (based on the id) gives you the end result..
WITH x AS(
SELECT
t.ID,
t.SYMPTOM1,
t.SYMPTOM2,
ROW_NUMBER() OVER (PARTITION BY t.ID ORDER BY t.SYMPTOM1) as rn
FROM t
)
SELECT
*
FROM
x x1
LEFT JOIN x x2 ON x1.id = x2.id AND x1.rn = 1 AND x2.rn = 2
You can pivot on a row-number
SELECT
t.ID,
SYMPTOM1 = MAX(CASE WHEN t.rn = 1 THEN t.SYMPTOM1 END),
SYMPTOM2 = MAX(CASE WHEN t.rn = 1 THEN t.SYMPTOM2 END),
SYMPTOM3 = MAX(CASE WHEN t.rn = 2 THEN t.SYMPTOM1 END),
SYMPTOM4 = MAX(CASE WHEN t.rn = 2 THEN t.SYMPTOM2 END)
FROM (
SELECT
t.*,
rn = ROW_NUMBER() OVER (PARTITION BY t.ID ORDER BY (SELECT 1))
FROM YourTable t
) t
GROUP BY t.ID;
Related
I have data like
a-b where c = 1
a-b where c = 2
how to select 2 columns same table with different where clause
i have try
select (select a-b from t where c = 1),
(select a-b from t where c = 2)
from t
Thank u
Your code should work, but you can use conditional aggregation:
select max(case when c = 1 then a - b end),
max(case when c = 2 then a - b end)
from t;
I Have a table looks like this:
RowNum category Rank4A Rank4B
-------------------------------------------
1 A
2 A
3 B
5 A
6 B
9 B
My requirement is based on the RowNum order, Make two new ranking columns depend on category. Rank4A works like the DENSERANK() by category = A, but if the row is for category B, it derives the latest appeared rank for category A order by RowNum. Rank4B have similar logic, but it orders by RowNum in DESC order. So the result would like this (W means this cell I don't care its value):
RowNum category Rank4A Rank4B
-------------------------------------------
1 A 1 W
2 A 2 W
3 B 2 3
5 A 3 2
6 B W 2
9 B W 1
One more additional requirement is that CROSS APPLY or CURSOR is not allowed due to dataset being large. Any neat solutions?
Edit: Also no CTE (due to MAX 32767 limit)
You can use the following query:
SELECT RowNum, category,
SUM(CASE
WHEN category = 'A' THEN 1
ELSE 0
END) OVER (ORDER BY RowNum) AS Rank4A,
SUM(CASE
WHEN category = 'B' THEN 1
ELSE 0
END) OVER (ORDER BY RowNum DESC) AS Rank4B
FROM mytable
ORDER BY RowNum
Giorgos Betsos' answer is better, please read it first.
Try this out. I believe each CTE is clear enough to show the steps.
IF OBJECT_ID('tempdb..#Data') IS NOT NULL
DROP TABLE #Data
CREATE TABLE #Data (
RowNum INT,
Category CHAR(1))
INSERT INTO #Data (
RowNum,
Category)
VALUES
(1, 'A'),
(2, 'A'),
(3, 'B'),
(5, 'A'),
(6, 'B'),
(9, 'B')
;WITH AscendentDenseRanking AS
(
SELECT
D.RowNum,
D.Category,
AscendentDenseRanking = DENSE_RANK() OVER (ORDER BY D.Rownum ASC)
FROM
#Data AS D
WHERE
D.Category = 'A'
),
LaggedRankingA AS
(
SELECT
D.RowNum,
AscendentDenseRankingA = MAX(A.AscendentDenseRanking)
FROM
#Data AS D
INNER JOIN AscendentDenseRanking AS A ON D.RowNum > A.RowNum
WHERE
D.Category = 'B'
GROUP BY
D.RowNum
),
DescendantDenseRanking AS
(
SELECT
D.RowNum,
D.Category,
DescendantDenseRanking = DENSE_RANK() OVER (ORDER BY D.Rownum DESC)
FROM
#Data AS D
WHERE
D.Category = 'B'
),
LaggedRankingB AS
(
SELECT
D.RowNum,
AscendentDenseRankingB = MAX(A.DescendantDenseRanking)
FROM
#Data AS D
INNER JOIN DescendantDenseRanking AS A ON D.RowNum < A.RowNum
WHERE
D.Category = 'A'
GROUP BY
D.RowNum
)
SELECT
D.RowNum,
D.Category,
Rank4A = ISNULL(RA.AscendentDenseRanking, LA.AscendentDenseRankingA),
Rank4B = ISNULL(RB.DescendantDenseRanking, LB.AscendentDenseRankingB)
FROM
#Data AS D
LEFT JOIN AscendentDenseRanking AS RA ON D.RowNum = RA.RowNum
LEFT JOIN LaggedRankingA AS LA ON D.RowNum = LA.RowNum
LEFT JOIN DescendantDenseRanking AS RB ON D.RowNum = RB.RowNum
LEFT JOIN LaggedRankingB AS LB ON D.RowNum = LB.RowNum
/*
Results:
RowNum Category Rank4A Rank4B
----------- -------- -------------------- --------------------
1 A 1 3
2 A 2 3
3 B 2 3
5 A 3 2
6 B 3 2
9 B 3 1
*/
This isn't a recursive CTE, so the limit 32k doesn't apply.
I have following table
ID Name Stage
1 A 1
1 B 2
1 C 3
1 A 4
1 N 5
1 B 6
1 J 7
1 C 8
1 D 9
1 E 10
I need output as below with parameters A and N need to select closest rows where difference between stage is smallest
ID Name Stage
1 A 4
1 N 5
I need to select rows where difference between stage is smallest
This query can make use of an index on (name, stage) efficiently:
WITH cte AS (
SELECT TOP 1
a.id AS a_id, a.name AS a_name, a.stage AS a_stage
, n.id AS n_id, n.name AS n_name, n.stage AS n_stage
FROM tbl a
CROSS APPLY (
SELECT TOP 1 *, stage - a.stage AS diff
FROM tbl
WHERE name = 'N'
AND stage >= a.stage
ORDER BY stage
UNION ALL
SELECT TOP 1 *, a.stage - stage AS diff
FROM tbl
WHERE name = 'N'
AND stage < a.stage
ORDER BY stage DESC
) n
WHERE a.name = 'A'
ORDER BY diff
)
SELECT a_id AS id, a_name AS name, a_stage AS stage FROM cte
UNION ALL
SELECT n_id, n_name, n_stage FROM cte;
SQL Server uses CROSS APPLY in place of standard-SQL LATERAL.
In case of ties (equal difference) the winner is arbitrary, unless you add more ORDER BY expressions as tiebreaker.
dbfiddle here
This solution works, if u know the minimum difference is always 1
SELECT *
FROM myTable as a
CROSS JOIN myTable as b
where a.stage-b.stage=1;
a.ID a.Name a.Stage b.ID b.Name b.Stage
1 A 4 1 N 5
Or simpler if u don't know the minimum
SELECT *
FROM myTable as a
CROSS JOIN myTable as b
where a.stage-b.stage in (SELECT min (a.stage-b.stage)
FROM myTable as a
CROSS JOIN myTable as b)
I realise this maybe similar to other questions, but I am stuck!
I am having trouble organising some data into an appropriate format to export to another tool. Basically I have an ID column and then 2 response columns. I would like to separate the ID and then list the responses under each. See the example below for clarification.
I have played around with Pivot and UnPivot but can't get it quite right.
Here is how the data looks now.
ID X1 X2
1 2 Y
1 5 Y
1 3 N
1 7 N
1 6 Y
2 5 N
2 4 Y
2 8 Y
2 3 N
3 5 Y
3 1 N
3 9 N
Here is how I would like the data to look
ID1_X1 ID1_X2 ID2_X1 ID2_X2 ID3_X1 ID3_X2
2 Y 5 N 5 Y
5 Y 4 Y 1 N
3 N 8 Y 9 N
7 N 3 N null null
6 Y null null null null
Here is the code to create/populate the table.
create table #test (ID int, X1 int, X2 varchar(1))
insert into #test values
('1','2','Y'),('1','5','Y'),('1','3','N'),('1','7','N'),
('1','6','Y'),('2','5','N'),('2','4','Y'),('2','8','Y'),
('2','3','N'),('3','5','Y'),('3','1','N'),('3','9','N')
You can do this using aggregation and row_number() . . . assuming you know the ids in advance:
select max(case when id = 1 then x1 end) as x1_1,
max(case when id = 1 then x2 end) as x2_1,
max(case when id = 2 then x1 end) as x1_2,
max(case when id = 2 then x2 end) as x2_2,
max(case when id = 3 then x1 end) as x1_3,
max(case when id = 3 then x2 end) as x2_3
from (select t.*,
row_number() over (partition by id order by (select null)) a seqnum
from #test t
) t
group by seqnum;
I should note that SQL tables represent unordered sets. Your original data doesn't have an indication of the ordering, so this is not guaranteed to put the values in the same order as the original data (actually, there is no such order that that statement is a tautology). If you have another column with the ordering, then you can use that.
Here is a alternative approach to Gordan's good answer using OUTER JOIN's
Considering that there is a Identity column in your table to define the order of X1 in each ID and fixed number of ID's
;WITH FST
AS (SELECT ROW_NUMBER()OVER(ORDER BY IDENTITY_COL) RN,X1 AS ID1_X1,X2 AS ID1_X2
FROM #TEST A
WHERE ID = 1),
SCD
AS (SELECT ROW_NUMBER()OVER(ORDER BY IDENTITY_COL) RN,X1 AS ID2_X1,X2 AS ID2_X2
FROM #TEST A
WHERE ID = 2),
TRD
AS (SELECT ROW_NUMBER()OVER(ORDER BY IDENTITY_COL) RN,X1 AS ID3_X1,X2 AS ID3_X2
FROM #TEST A
WHERE ID = 3)
SELECT ID1_X1,ID1_X2,ID2_X1,ID2_X2,ID3_X1,ID3_X2
FROM FST A
FULL OUTER JOIN SCD B
ON A.RN = B.RN
FULL OUTER JOIN TRD C
ON C.RN = COALESCE(B.RN, A.RN)
I have the following table:
Name Field
A 1
B 1
C 1
D 1
E 1
F 1
G 1
H 2
I 2
J 2
K 3
L 3
M 3
N 3
O 3
P 3
Q 3
R 3
S 3
T 3
I need a SQL query which will generate me a set with 5 random rows for each distinct value on column Field.
For example, results expected:
Name Field
A 1
B 1
D 1
E 1
G 1
J 2
I 2
H 2
M 3
Q 3
T 3
S 3
P 3
Is there an easy way to do this? Or should i split that table into more tables and generate random for each table then union them?
You can do this with a CTE using a ROW_NUMBER() whilst PARTITIONing on the Field:
;With Cte As
(
Select Name, Field,
Row_Number() Over (Partition By Field Order By NewId()) RN
From YourTable
)
Select Name, Field
From Cte
Where RN <= 5
SQL Fiddle
You can readily do this with row_number():
select name, field
from (select t.*,
row_number() over (partition by field order by newid()) as seqnum
from t
) t
where seqnum <= 5;
An enhancement to Gordon Linoff's code, This code really helped me if you need criteria in your query.
select *
from (select t.*,
row_number() over (partition by region order by newid()) as seqnum
from MyTable t
WHERE t.program = 'ACME'
) t
where seqnum <= 1500;