"Distinct" column in SQL query - sql-server-2005

SELECT id, EmpNo
FROM EmployeesTable
EmpNo can be the same for 1 or more records in the results of the above query. I now want to add another column derived from EmpNo(lets call it EmpNo2) but only returning distinct values of EmpNo.
For example if the above query returns 100 records but there are 69 distinct EmpNo values and i modify the query to
SELECT id, EmpNo, Distinct EmpNo2
FROM EmployeesTable EmpNo
,
i want all the 100 rows to be returned but the last column EmpNo2 should return 69 distinct values of EmpNo field.
But as already know, using distinct in that way results into an error but i want to implement such functionality - and a subquery is not helping.
SAMPLE REQUIRED RESULTS
ID EmpNo EmpNo2
1 0T4/HR 0T4/HR
1 0T4/HR 2VP/E
1 0T4/HR xT9/67
1 0T4/HR
1 0T4/HR
2 2VP/E
2 2VP/E
2 2VP/E
2 2VP/E
2 2VP/E
3 XT9/67
3 XT9/67
3 xT9/67
3 XT9/67

How about:
Select id, empno, empno2
from employeestable left outer join (
SELECT min([id]) as minid
,[empno] empno2
FROM [EmployeesTable]
group by empno) etab2 on employeestable.id = etab2.minid
You're saying a subquery won't work, though - why not?

Your requirement is not clear and I also have very little information. Following is what you need. This can be even better but it is just a try.
declare #temp table
(
uniqueid int identity(1, 1),
id int,
empno varchar(50),
empno2 varchar(50)
)
insert into #temp select 1, '0T4/HR', null
insert into #temp select 1, '0T4/HR' , null
insert into #temp select 1 , '0T4/HR' , null
insert into #temp select 1, '0T4/HR' , null
insert into #temp select 1, '0T4/HR' , null
insert into #temp select 2, '2VP/E' , null
insert into #temp select 2, '2VP/E' , null
insert into #temp select 2, '2VP/E' , null
insert into #temp select 2, '2VP/E' , null
insert into #temp select 2, '2VP/E' , null
insert into #temp select 3, 'XT9/67' , null
insert into #temp select 3, 'XT9/67' , null
insert into #temp select 3, 'xT9/67' , null
insert into #temp select 3, 'XT9/67' , null
SELECT ROW_NUMBER() OVER (ORDER BY id) AS id, empno into #temp FROM #temp group by empno, id
update #temp set empno2 = t2.empno
from #temp t inner join #temp t2 on t.uniqueid = t2.id
select * from #temp
drop table #temp

Related

How to get the each record with some condition

I have following data:
DECLARE #temp TABLE (
ID int
,sn varchar(200)
,comment varchar(2000)
,rownumber int
)
insert into #temp values(1,'sn1',NULL,1)
insert into #temp values(2,'sn1','aaa',2)
insert into #temp values(3,'sn1','bbb',3)
insert into #temp values(4,'sn1',NULL,4)
insert into #temp values(5,'sn2',NULL,1)
insert into #temp values(6,'sn2',NULL,2)
insert into #temp values(7,'sn2',NULL,3)
select * from #temp
And I want to output like this:
2 sn1 aaa 2
5 sn2 NULL 1
same sn, if comment have value, get this lower rownumber's record. For sn1, have two records with comment value, so here, get the the record with rownumber=2
If comment doesn't have value, get the lower rownumber's record. For sn2, get the record with rownumber=1
May I know how to write this SQL?
This is a prioritization query. I think row_number() is the simplest method:
select t.*
from (select t.*,
row_number() over (partition by sn
order by (case when comment is not null then 1 else 2 end),
rownumber
) as seqnum
from #temp t
) t
where seqnum = 1;
Here is a db<>fiddle.

Insert multiple row different column value

This is my existing table
In this table, each user has their own respective data according to their Status. Each of the user will surely have Status 1.
Now, there are 3 Status to be stored for every user.
Was trying to make every user to have 3 Status, by inserting new row of user copying their Status 1 data, such that:
User Ali currently only have Status 1 and its data, so need insert a new
row Ali with Status 2 and copy along the data from Status 1, again,
insert a new row Ali with Status 3 and copy along the data from
Status 1.
User John currently only have Status 1 and 2, so need insert a new
row John with Status 3 and copy along the data from Status 1.
continue same pattern with other user
Expected result:
I would use CROSS JOIN and NOT EXISTS
with data as
(
select name,
column1,
column2
from your_table
where status = 1
), cross_join_data as
(
select d1.name, t.status, d1.column1, d1.column2
from data d1
cross join
(
select 1 status
union
select 2 status
union
select 3 status
) t
where not exists (
select 1
from your_table d2
where d2.name = d1.name and
d2.status = t.status
)
)
select *
from your_table
union all
select *
from cross_join_data
dbfiddle demo
This should work
with cte as (
select
[Name], coalesce(max(iif([Status]=1, [Column1], null)), max(iif([Status]=2, [Column1], null)), max(iif([Status]=3, [Column1], null))) col1
, coalesce(max(iif([Status]=1, [Column2], null)), max(iif([Status]=2, [Column2], null)), max(iif([Status]=3, [Column2], null))) col2
from
MyTable
group by [Name]
)
--insert into MyTable
select
cte.[Name], nums.n, cte.col1, cte.col2
from
cte
cross join (values (1),(2),(3)) nums(n)
left join MyTable on cte.[Name]=MyTable.[Name] and n=MyTable.[Status]
where
MyTable.[Status] is null
This works if data is not nullable
declare #table table (name varchar(10), status int, data int);
insert into #table values
('a', 1, 2)
, ('a', 2, 5)
, ('a', 3, 7)
, ('b', 1, 5)
, ('b', 2, 6)
, ('c', 1, 3)
select stats.status as statusStats
, tn.name as nameTN
, t.status as statusData, t.name, t.data
, ISNULL(t.data, t1.data) as 'fillInData'
from (values (1),(2),(3)) as stats(status)
cross join (select distinct name from #table) tn
left join #table t
on t.status = stats.status
and t.name = tn.name
join #table t1
on t1.name = tn.name
and t1.status = 1
order by tn.name, stats.status
Here is what I would do:
CREATE TABLE #existingtable (Name VARCHAR(50), Status INT, Column1 VARCHAR (10), Column2 VARCHAR(10));
INSERT INTO #existingtable (Name,Status,Column1,Column2) Values('Ali',1,'100','90');
INSERT INTO #existingtable (Name,Status,Column1,Column2) Values('John',1,'20','200');
INSERT INTO #existingtable (Name,Status,Column1,Column2) Values('John',2,'80','90');
INSERT INTO #existingtable (Name,Status,Column1,Column2) Values('Ming',1,'54','345');
INSERT INTO #existingtable (Name,Status,Column1,Column2) Values('Mei',1,'421','123');
INSERT INTO #existingtable (Name,Status,Column1,Column2) Values('Mei',3,'24','344');
SELECT * FROM #existingtable;
WITH CTE (Name,Column1,Column2)
AS
(
SELECT DISTINCT NAME,COLUMN1,COLUMN2
FROM #existingtable
)
, CTE2 (NAME,Status,Column1,Column2)
AS
(
SELECT NAME,1 AS STATUS,COLUMN1,COLUMN2
FROM CTE
UNION
SELECT NAME,2 AS STATUS,COLUMN1,COLUMN2
FROM CTE
UNION
SELECT NAME,3 AS STATUS,COLUMN1,COLUMN2
FROM CTE
)
INSERT INTO #existingtable (Name,Status,Column1,Column2)
SELECT C.Name,C.Status,C.Column1,C.Column2
FROM CTE2 AS C
LEFT JOIN #existingtable AS E
ON C.NAME = E.Name
AND C.Status = E.Status
WHERE E.Status IS NULL
SELECT * FROM #existingtable
ORDER BY Name, status
This has 2 edits. Initial edit added a where clause to the CTE
Second edit added the values added by the OP

Subquery: how to retrieve the last non-zero value from a column?

Considering a table customerBalance with 3 columns: name, date and balance. Suppose a set of records like:
cus_name cus_date cus_balance
John 06/14/2011 1000
John 06/15/2011 500
John 06/16/2011 0
Mary 06/14/2011 3000
Mary 06/15/2011 2800
Mary 06/16/2011 0
How to create a SQL query which returns, for the date 6/16/2011 instead 0, the last non-zero value based on date (in sample, $500 for John and $2800 for Mary)?
I'm trying to do it using a subquery which uses Max function to retrieve the last date with non-zero value, but I didn't succeed. This example is quite "nonsensical", but I really need to do an operation like this in my dataset. Thanks!
Note: If you can specify the DB and version this query can be improved.
Try this:
SELECT *
FROM customers
WHERE (cus_name, cus_date)
IN
(
SELECT cus_name, MAX(cus_date)
FROM customers
WHERE cus_balance <> 0
GROUP BY cus_name
)
Update: Alternate version:
SELECT a.*
FROM customers a,
(
SELECT cus_name, MAX(cus_date)
FROM customers
WHERE cus_balance <> 0
GROUP BY cus_name
) b
WHERE a.cus_name = b.cus_name
AND a.cus_date = b.cus_date
Here it goes:
CREATE Table #temp
(
Cus_Name VARCHAR(200) NULL,
Cus_Date Char(8) NULL,
Cus_Balance INT NULL
)
INSERT INTO #temp VALUES ('John' , '20110614' ,1000 )
INSERT INTO #temp VALUES ('John' , '20110615' , 500 )
INSERT INTO #temp VALUES ('John' , '20110616' , 0 )
INSERT INTO #temp VALUES ('Mary' , '20110614' ,3000 )
INSERT INTO #temp VALUES ('Mary' , '20110615' ,2800 )
INSERT INTO #temp VALUES ('Mary' , '20110616' , 0 )
SELECT
T.Cus_Name ,
MIN(t.Cus_Balance)
FROM #temp t
WHERE t.Cus_Balance <>0
GROUP BY t.Cus_Name
DROP TABLE #temp

t-sql recursive query

Based on an existing table I used CTE recursive query to come up with following data. But failing to apply it a level further.
Data is as below
id name parentid
--------------------------
1 project 0
2 structure 1
3 path_1 2
4 path_2 2
5 path_3 2
6 path_4 3
7 path_5 4
8 path_6 5
I want to recursively form full paths from the above data. Means the recursion will give the following output.
FullPaths
-------------
Project
Project\Structure
Project\Structure\Path_1
Project\Structure\Path_2
Project\Structure\Path_3
Project\Structure\Path_1\path_4
Project\Structure\Path_2\path_5
Project\Structure\Path_3\path_6
Thanks
Here's an example CTE to do that:
declare #t table (id int, name varchar(max), parentid int)
insert into #t select 1, 'project' , 0
union all select 2, 'structure' , 1
union all select 3, 'path_1' , 2
union all select 4, 'path_2' , 2
union all select 5, 'path_3' , 2
union all select 6, 'path_4' , 3
union all select 7, 'path_5' , 4
union all select 8, 'path_6' , 5
; with CteAlias as (
select id, name, parentid
from #t t
where t.parentid = 0
union all
select t.id, parent.name + '\' + t.name, t.parentid
from #t t
inner join CteAlias parent on t.parentid = parent.id
)
select *
from CteAlias
Try something like this:
WITH Recursive AS
(
SELECT
ID,
CAST(PathName AS VARCHAR(500)) AS 'FullPaths',
1 AS 'Level'
FROM
dbo.YourTable
WHERE
ParentID = 0
UNION ALL
SELECT
tbl.ID,
CAST(r.FullPaths + '\' + tbl.PathName AS VARCHAR(500)) AS 'FullPaths',
r.Level + 1 AS 'Level'
FROM
dbo.YourTable tbl
INNER JOIN
Recursive r ON tbl.ParentID = r.ID
)
SELECT * FROM Recursive
ORDER BY Level, ID
Output:
ID FullPaths Level
1 project 1
2 project\structure 2
3 project\structure\path_1 3
4 project\structure\path_2 3
5 project\structure\path_3 3
6 project\structure\path_1\path_4 4
7 project\structure\path_2\path_5 4
8 project\structure\path_3\path_6 4
try this:
DECLARE #YourTable table (id int, nameof varchar(25), parentid int)
INSERT #YourTable VALUES (1,'project',0)
INSERT #YourTable VALUES (2,'structure',1)
INSERT #YourTable VALUES (3,'path_1',2)
INSERT #YourTable VALUES (4,'path_2',2)
INSERT #YourTable VALUES (5,'path_3',2)
INSERT #YourTable VALUES (6,'path_4',3)
INSERT #YourTable VALUES (7,'path_5',4)
INSERT #YourTable VALUES (8,'path_6',5)
;WITH Rec AS
(
SELECT
CONVERT(varchar(max),nameof) as nameof,id
FROM #YourTable
WHERE parentid=0
UNION ALL
SELECT
CONVERT(varchar(max),r.nameof+'\'+y.nameof), y.id
FROM #yourTable y
INNER jOIN Rec r ON y.parentid=r.id
)
select * from rec
output:
nameof
-----------------------------------------------
project
project\structure
project\structure\path_1
project\structure\path_2
project\structure\path_3
project\structure\path_3\path_6
project\structure\path_2\path_5
project\structure\path_1\path_4
(8 row(s) affected)
Something like
;WITH MyCTE AS
(
SELECT
name AS FullPaths, id
FROM
MyTable
WHERE
parentid = 0 /*Normally it'd be IS NULL with an FK linking the 2 columns*/
UNION ALL
SELECT
C.FullPaths + '\' + M.name, M.id
FROM
MyCTE C
JOIN
MyTable M ON M.parentid = C.id
)
SELECT FullPaths FROM MyCTE
You'll have to change the name of #test table I was using.
WITH cte(id, name, parentid) AS
(
SELECT id, convert(varchar(128), name), parentid
FROM #test
WHERE parentid = 0
UNION ALL
SELECT t.id, convert(varchar(128), c.name +'\'+t.name), t.parentid
FROM #test t
INNER JOIN cte c
ON c.id = t.parentid
)
SELECT name as FullPaths
FROM cte
order by id

SQL Server + Select only two records for each masterID in a table

I got a child table that contains 1 to n records linked to the master table via a MasterID column.
How can I select from the child table only the first 5 records for each MasterID?
Using Sql Server CTE and ROW_NUMBER you could try using
DECLARE #ParentTable TABLE(
ID INT
)
INSERT INTO #ParentTable SELECT 1
INSERT INTO #ParentTable SELECT 2
INSERT INTO #ParentTable SELECT 3
DECLARE #ChildTable TABLE(
ID INT,
ParentID INT
)
INSERT INTO #ChildTable SELECT 1, 1
INSERT INTO #ChildTable SELECT 2, 1
INSERT INTO #ChildTable SELECT 3, 1
INSERT INTO #ChildTable SELECT 4, 1
INSERT INTO #ChildTable SELECT 5, 1
INSERT INTO #ChildTable SELECT 6, 1
INSERT INTO #ChildTable SELECT 7, 1
INSERT INTO #ChildTable SELECT 8, 2
INSERT INTO #ChildTable SELECT 9, 2
INSERT INTO #ChildTable SELECT 10, 3
INSERT INTO #ChildTable SELECT 11, 3
;WITH RowNums AS(
SELECT pt.ID ParentID,
ct.ID ChildID,
ROW_NUMBER() OVER (PARTITION BY pt.ID ORDER BY ct.ID) RowNum
FROM #ParentTable pt INNER JOIN
#ChildTable ct ON pt.ID = ct.ParentID
)
SELECT ParentID,
ChildID
FROM RowNums
WHERE RowNum <= 5
Try a regular join where the constraint is a subquery pulling the TOP 5 from the child table. In untested pseudocode:
SELECT A.MasterID, B.*
FROM MasterTable A
JOIN ChildTable B
ON A.MasterID = B.MasterID
AND B.ChildID IN (SELECT Top 5 ChildID FROM ChildTable
WHERE MasterID = A.MasterID ORDER BY Whatever)