I have the below table where names will be inserted first. Then I will get IDs where I need to map with names
ID NAME
null Test1
null Test2
1 null
2 null
I need the result like
ID NAME
1 Test1
2 Test2
I tried below query but it doesn't work for me
select t1.ID , t2.Name from table1 T1 join table1 t2 on T1.id = t2.id
According to screen short you are working with SQL Server , you could try cte expression which may help you
;with cte as
(
select max(id) id, row_number() over (order by (select 1)) rn from
(
select *, rank() over(order by id) rnk from table
) a
group by a.rnk
having max(id) is not null
), cte1 as
(
select max(name) name, row_number() over (order by (select 1)) rn from
(
select *, rank() over(order by name) rnk from table
) a
group by a.rnk
having max(name) is not null
)
select c.id, c1.name from cte c
join cte1 c1 on c1.rn = c.rn
Result :
id name
1 test1
2 test2
Related
In SQL Server, I have the following table:
Name New_Name
---------------
A B
B C
C D
G H
H I
Z B
I want to create a new table that links all the names that are related to a single new groupID
GroupID Name
-------------
1 A
1 B
1 C
1 D
1 Z
2 G
2 H
2 I
I'm a bit stuck on this can can't figure out how to do it apart from a bunch of joins. But I would like to do it properly.
Edited the question to allow grouping from two different start points, A and Z into one group.
Since you've changed the question, I'm updating the answer. Please note that answer is same in sense of logical structure. All it does differently is that instead of going from G to I in calculating levels, answer now calculates from I to G.
Working demo link
;with cte as
(
select
t1.Name as Name, row_number() over (order by t1.Name) r,
t1.New_Name as New_Name,
1 as level
from yt t1 left join yt t2
on t1.New_Name=t2.name
where t2.name is null
union all
select
yt.Name as Name, r,
yt.New_Name as New_Name,
c.level+1 as level
from cte c join yt
on yt.New_Name=c.Name
),
cte2 as
(
select r as group_id, Name from cte
union
select c1.r as group_id, c1.New_name as Name from cte c1
where level = (select min(level) from cte c2 where c2.r=c1.r)
)
select * from cte2;
Below is old answer.
You can try below CTE based query:
create table yt (Name varchar(10), New_Name varchar(10));
insert into yt values
('A','B'),
('B','C'),
('C','D'),
('G','H'),
('H','I');
;with cte as
(
select
t1.Name as Name, row_number() over (order by t1.Name) r,
t1.New_Name as New_Name,
1 as level
from yt t1 left join yt t2
on t1.Name=t2.New_name
where t2.new_name is null
union all
select
yt.Name as Name, r,
yt.New_Name as New_Name,
c.level+1 as level
from cte c join yt
on yt.Name=c.New_Name
),
cte2 as
(
select r as group_id, Name from cte
union
select c1.r as group_id, c1.New_name as Name from cte c1
where level = (select max(level) from cte c2 where c2.r=c1.r)
)
select * from cte2;
see working demo
Little bit complex but working.
DECLARE #T TABLE (Name VARCHAR(2), New_Name VARCHAR(2))
INSERT INTO #T
VALUES
('A','B'),
('B','C'),
('C','D'),
('G','H'),
('H','I'),
('Z','B')
;WITH CTE AS
(
SELECT * , RN = ROW_NUMBER() OVER(ORDER BY Name) FROM #T
)
,CTE2 AS (SELECT T1.RN, T1.Name Name1, T1.New_Name New_Name1,
X.Name Name2, X.New_Name New_Name2,
FLAG = CASE WHEN X.Name IS NULL THEN 1 ELSE 0 END
FROM CTE T1
OUTER APPLY (SELECT * FROM CTE T2 WHERE T2.RN > T1.RN
AND (T2.Name IN (T1.Name , T1.New_Name)
OR T2.New_Name IN (T1.Name , T1.New_Name)
)) AS X
)
,CTE3 AS (SELECT *,
GroupID = ROW_NUMBER() OVER (ORDER BY RN) -
ROW_NUMBER() OVER (PARTITION BY Flag ORDER BY RN) +1
FROM CTE2
)
SELECT
DISTINCT GroupID, Name
FROM
(SELECT * FROM CTE3 WHERE Name2 IS NOT NULL) SRC
UNPIVOT ( Name FOR COL IN ([Name1], [New_Name1], [Name2], [New_Name2])) UNPVT
Result
GroupID Name
-------------------- ----
1 A
1 B
1 C
1 D
1 Z
2 G
2 H
2 I
I have this table:
TableA
----------------
ID (pk) Name
1 A
2 B
3 C
4 A
5 D
6 A
7 B
8 A
9 D
10 C
....
I need to randomly extract with a SELECT TOP 5 ID, Name FROM TableA
with Name that must be unique within the 5 records.
I'm trying :
;WITH group
AS
(
SELECT ID, Name,
ROW_NUMBER() OVER (PARTITION BY Name ORDER BY NewId()) rn
FROM TableA
)
SELECT ID, Name
FROM group
WHERE rn = 1
but every time I have quite the same results.
I need to select between all the values for ID at random, assuring that Name will always be different for each record.
I hope the problem is understandable. Any ideas?
Found a solution. It seems to work!
;WITH group
AS (
SELECT ID, Name, ROW_NUMBER() OVER (PARTITION BY Name ORDER BY NewId()) rn FROM TableA )
SELECT top 5 ID, Name, NewId() [NewId]
FROM group
WHERE rn = 1
ORDER BY [newid]
Perhaps the problem is that although newid() is random, it may tend to be sequential. Does this fix the problem?
WITH g as (
SELECT ID, Name,
ROW_NUMBER() OVER (PARTITION BY Name ORDER BY RAND(CHECKSUM(NewId()))) as rn
FROM TableA
)
SELECT ID, Name
FROM g
WHERE rn = 1;
CREATE TABLE #test(ID INT ,Name VARCHAR(1)) INSERT INTO #test(ID ,Name )
SELECT 1,'A' UNION ALL SELECT 2,'B' UNION ALL SELECT 3,'C' UNION ALL
SELECT 4,'A' UNION ALL SELECT 5,'D'UNION ALL SELECT 6,'A' UNION ALL
SELECT 7,'B' UNION ALL SELECT 8,'A'UNION ALL SELECT 9,'D' UNION ALL
SELECT 10,'C'
SELECT T1.ID ,T1.Name FROM #test T1
JOIN ( SELECT TOP 5 Name FROM #test T2 ORDER BY NEWID()
) A ON T1.Name = A.Name ORDER BY A.Name
;WITH group
AS
(
SELECT ID, Name,
ROW_NUMBER() OVER (PARTITION BY Name ORDER BY NewId()) rn
FROM TableA
)
SELECT top 5 ID, Name, NewId() [NewId]
FROM group
WHERE rn = 1
ORDER BY [newid]
I want to join table 1 with table2 twice becuase I need to get the first minimum record and the second minimum. However, I can only think of using a cte to get the second minimum record. Is there a better way to do it?
Here is the table table:
I want to join Member with output table FirstRunID whose Output value is 1 and second RunID whose Output value is 0
current code I am using:
select memid, a.runid as aRunid,b.runid as bRunid
into #temp
from FirstTable m inner join
(select min(RunID), MemID [SecondTable] where ouput=1 group by memid)a on m.memid=a.memid
inner join (select RunID, MemID [SecondTable] where ouput=0 )b on m.memid=a.memid and b.runid>a.runid
with cte as
(
select row_number() over(partition by memid, arunid order by brunid ),* from #temp
)
select * from cte where n=1
You can use outer apply operator for this:
select * from t1
outer apply(select top 1 t2.runid from t2
where t1.memid = t2.memid and t2.output = 1 order by t2.runid) as oa1
outer apply(select top 1 t2.runid from t2
where t1.memid = t2.memid and t2.output = 0 order by t2.runid) as oa2
You can do this with conditional aggregation. Based on your results, you don't need the first table:
select t2.memid,
max(case when output = 1 and seqnum = 1 then runid end) as OutputValue1,
max(case when output = 0 and seqnum = 2 then runid end) as OutputValue2
from (select t2.*,
row_number() over (partition by memid, output order by runid) a seqnum
from t2
) t2
group by t2.memid;
declare #FirstTable table
(memid int, name varchar(20))
insert into #firsttable
values
(1,'John'),
(2,'Victor')
declare #secondtable table
(runid int,memid int,output int)
insert into #secondtable
values
(1,1,0),(1,2,1),(2,1,1),(2,2,1),(3,1,1),(3,2,0),(4,1,0),(4,2,0)
;with cte as
(
SELECT *, row_number() over (partition by memid order by runid) seq --sequence
FROM #SECONDTABLE T
where t.output = 1
union all
SELECT *, row_number() over (partition by memid order by runid) seq --sequence
FROM #SECONDTABLE T
where t.output = 0 and
t.runid > (select min(x.runid) from #secondtable x where x.memid = t.memid and x.output = 1 group by x.memid) --lose any O output record where there is no prior 1 output record
)
select cte1.memid,cte1.runid,cte2.runid from cte cte1
join cte cte2 on cte2.memid = cte1.memid and cte2.seq = cte1.seq
where cte1.seq = 1 --remove this test if you want matched pairs
and cte1.output = 1 and cte2.output = 0
I need to concatenate the name in a recursive cross join way. I don't know how to do this, I have tried a CTE using WITH RECURSIVE but no success.
I have a table like this:
group_id | name
---------------
13 | A
13 | B
19 | C
19 | D
31 | E
31 | F
31 | G
Desired output:
combinations
------------
ACE
ACF
ACG
ADE
ADF
ADG
BCE
BCF
BCG
BDE
BDF
BDG
Of course, the results should multiply if I add a 4th (or more) group.
Native Postgresql Syntax:
SqlFiddleDemo
WITH RECURSIVE cte1 AS
(
SELECT *, DENSE_RANK() OVER (ORDER BY group_id) AS rn
FROM mytable
),cte2 AS
(
SELECT
CAST(name AS VARCHAR(4000)) AS name,
rn
FROM cte1
WHERE rn = 1
UNION ALL
SELECT
CAST(CONCAT(c2.name,c1.name) AS VARCHAR(4000)) AS name
,c1.rn
FROM cte1 c1
JOIN cte2 c2
ON c1.rn = c2.rn + 1
)
SELECT name as combinations
FROM cte2
WHERE LENGTH(name) = (SELECT MAX(rn) FROM cte1)
ORDER BY name;
Before:
I hope if you don't mind that I use SQL Server Syntax:
Sample:
CREATE TABLE #mytable(
ID INTEGER NOT NULL
,TYPE VARCHAR(MAX) NOT NULL
);
INSERT INTO #mytable(ID,TYPE) VALUES (13,'A');
INSERT INTO #mytable(ID,TYPE) VALUES (13,'B');
INSERT INTO #mytable(ID,TYPE) VALUES (19,'C');
INSERT INTO #mytable(ID,TYPE) VALUES (19,'D');
INSERT INTO #mytable(ID,TYPE) VALUES (31,'E');
INSERT INTO #mytable(ID,TYPE) VALUES (31,'F');
INSERT INTO #mytable(ID,TYPE) VALUES (31,'G');
Main query:
WITH cte1 AS
(
SELECT *, rn = DENSE_RANK() OVER (ORDER BY ID)
FROM #mytable
),cte2 AS
(
SELECT
TYPE = CAST(TYPE AS VARCHAR(MAX)),
rn
FROM cte1
WHERE rn = 1
UNION ALL
SELECT
[Type] = CAST(CONCAT(c2.TYPE,c1.TYPE) AS VARCHAR(MAX))
,c1.rn
FROM cte1 c1
JOIN cte2 c2
ON c1.rn = c2.rn + 1
)
SELECT *
FROM cte2
WHERE LEN(Type) = (SELECT MAX(rn) FROM cte1)
ORDER BY Type;
LiveDemo
I've assumed that the order of "cross join" is dependent on ascending ID.
cte1 generate DENSE_RANK() because your IDs contain gaps
cte2 recursive part with CONCAT
main query just filter out required length and sort string
The recursive query is a bit simpler in Postgres:
WITH RECURSIVE t AS ( -- to produce gapless group numbers
SELECT dense_rank() OVER (ORDER BY group_id) AS grp, name
FROM tbl
)
, cte AS (
SELECT grp, name
FROM t
WHERE grp = 1
UNION ALL
SELECT t.grp, c.name || t.name
FROM cte c
JOIN t ON t.grp = c.grp + 1
)
SELECT name AS combi
FROM cte
WHERE grp = (SELECT max(grp) FROM t)
ORDER BY 1;
The basic logic is the same as in the SQL Server version provided by #lad2025, I added a couple of minor improvements.
Or you can use a simple version if your maximum number of groups is not too big (can't be very big, really, since the result set grows exponentially). For a maximum of 5 groups:
WITH t AS ( -- to produce gapless group numbers
SELECT dense_rank() OVER (ORDER BY group_id) AS grp, name AS n
FROM tbl
)
SELECT concat(t1.n, t2.n, t3.n, t4.n, t5.n) AS combi
FROM (SELECT n FROM t WHERE grp = 1) t1
LEFT JOIN (SELECT n FROM t WHERE grp = 2) t2 ON true
LEFT JOIN (SELECT n FROM t WHERE grp = 3) t3 ON true
LEFT JOIN (SELECT n FROM t WHERE grp = 4) t4 ON true
LEFT JOIN (SELECT n FROM t WHERE grp = 5) t5 ON true
ORDER BY 1;
Probably faster for few groups. LEFT JOIN .. ON true makes this work even if higher levels are missing. concat() ignores NULL values. Test with EXPLAIN ANALYZE to be sure.
SQL Fiddle showing both.
Assume the following table:
Select *
from TestTable;
Name value
B 3
C 1
A 2
I want to output as follows:
Name value
A 1
B 2
C 3
Notice that in the result Names are matched to their corresponding ordinal values from the value column.
Anyone help, how can I write the SQL statement?
select
Name, Value
from
-- Order the Name table
(select row_number() over (order by name) as id, Name from TestTable) as n
inner join
-- Order the Value table
(select row_number() over (order by value) as id, Value from TestTable) as v
on n.id = v.id -- Combine two table by the ordered id
SELECT A.Name, B.Value FROM (
SELECT ROW_NUMBER() OVER(ORDER BY Name) as N, Name FROM Tab ) as A
INNER JOIN (SELECT ROW_NUMBER() OVER(ORDER BY Value) as N, Value FROM Tab) as B on B.N = A.N
WITH
test1 AS
(SELECT ROW_NUMBER() over(order by Name)as id , Name FROM Testing ),
test2 AS
(SELECT ROW_NUMBER() over(order by value)as id , value FROM Testing )
SELECT Name,Value
FROM test1
JOIN test2
ON test1.id=test2.id