I am currently working on Microsoft Access an I am struggling to do what I want.
I have this table A:
Table A
id title name date
123 azer dfgd 1
123 afg qsd 5
123 arr poi 7
123 aur qhg 3
456 aoe aer 3
456 iuy zer 4
And I would like to get the columns id,title and name that have the latest date (highest number) for each id
With that example, the query would give
id title name date
123 arr poi 7
456 iuy zer 4
I hope you'll be able to help me.
Thanks in advance !
I would recommend a correlated subquery:
select a.*
from a
where a.date = (select max(a2.date) from a as a2 where a2.id = a.id);
For performance, you want an index on a(id, date).
With NOT EXISTS:
select t.*
from tablename t
where not exists (
select 1 from tablename
where id = t.id and date > t.date
)
Related
I'm looking to narrow down my database to have only the most records. The most recent records need to have a value in a specific field.
ID Account_nbr Date Name
1 622 7/10/2018 Stu
2 622 7/24/2018
3 151 7/18/2018 Taylor
4 151 7/24/2018 Taylor
This is an example of the database.
I want the code to do this:
ID Account_nbr Date Name
1 622 7/10/2018 Stu
4 151 7/24/2018 Taylor
I have tried the following code:
Select m.*
FROM [table] m
INNER JOIN
(
SELECT last(Date) as LatestDate
,account_nbr
FROM [table]
WHERE Name IS NOT NULL
GROUP BY account_nbr
) b
ON m.Date = b.LatestDate
AND m.account_nbr = b.account_nbr
The output only included the most recent date and did not take into account records that were null in the name field.
I would do :
select t.*
from table as t
where t.name is not null and
t.date = (select max(t1.date)
from table as t1
where t1.account_nbr = t.account_nbr
);
Try this:
Select
m.*
From
[table] As m
Where
m.[Date] In
(Select Max([Date])
From [table] As T
Where T.[Name] Is Not Null
And T.account_nbr = m.account_nbr)
I tried below query to bring all rows after last Action="UNLOCKED", but ORDER BY is not allowed in subquery it seems.
SELECT *
FROM TABLE
WHERE id >= (SELECT MAX(id)
FROM TABLE
WHERE ACTION='UNLOCKED' AND action_id=123
ORDER BY CREATE_DATE DESC);
Sample data
Id action_id Action ... CREATE_DATE
1 123 ADD 03/18/2018
2 123 Unlocked 03/19/2018
3 123 Updated1 03/19/2018
4 123 Updated2 03/19/2018
5 123 Unlocked 03/20/2018
6 123 Updated3 03/20/2018
7 123 Updated4 03/20/2018
Output should be rows with id 5,6,7. What should i use to get this output
you could use an inner join on subselect for max create_date
select * from TABLE
INNER JOIN (
select max(CREATE_DATE) max_date
from TABLE
where Action = 'Unlocked' ) T on t.max_date = TABLE.CREATE_DATE
You need not order the inner query because it will return only one value. You can do it as follows
SELECT * FROM TABLE WHERE id >= (select max(id) from TABLE where ACTION='UNLOCKED' and action_id=123);
This seems easy, but I can't get it. Assume this dataset:
ID SID AddDate
1 123 1/1/2014
2 123 2/3/2015
3 123 1/4/2010
4 124
5 124
6 125 2/3/2012
7 126 2/2/2012
8 126 2/2/2011
9 126 2/2/2011
What I need is the most recent AddDate and the associated ID for each SID.
So, my dataset should return IDs 2, 5, 6 and 7
I tried doing a max(AddDate), but it won't give me the proper ID that's associated with it.
My SQL string:
SELECT First(Table1.ID) AS FirstOfID, Table1.SID, Max(Table1.AddDate) AS MaxOfAddDate
FROM Table1
GROUP BY Table1.SID;
You can use a subquery that returns the Maximum add date for each Sid, then you can join back this subquery to the dataset table:
SELECT
MAX(id)
FROM
ds INNER JOIN (
SELECT Sid, Max(AddDate) AS MaxAddDate
FROM ds
GROUP BY ds.Sid) mx
ON ds.Sid = mx.Sid AND (ds.AddDate=mx.MaxAddDate or MaxAddDate IS NULL)
GROUP BY
ds.Sid
the join still has to succeed if the MaxAddDate is NULL (there's no AddDate), and in case there are multiple ID that matches, it looks like you want the biggest one.
You can change your query to get the grouping first and then perform a JOIN like
SELECT First(Table1.ID) AS FirstOfID,
Table1.SID, xx.MaxOfAddDate
FROM Table1 JOIN (
SELECT ID, Max(AddDate) AS MaxOfAddDate
FROM Table1
GROUP BY SID) xx ON Table1.ID = xx.ID;
Try
select SID from table1
where addDate in (select max(addDate) from Table1)
I have a table like this
Table A:
Id Count
1 4
1 16
1 8
2 10
2 15
3 18
etc
Table B:
1 sample1.file
2 sample2.file
3 sample3.file
TABLE C:
Count fileNumber
16 1234
4 2345
15 3456
18 4567
and so on...
What I want is this
1 sample1.file 1234
2 sample2.file 3456
3 sample3.file 4567
To get the max value from table A I used
Select MAX (Count) from A where Id='1'
This works well but my problem is when combining data with another table.
When I join Table B and Table A, I need to get the MAX for all Ids and in my query I dont know what Id is.
This is my query
SELECT B.*,C.*
JOIN A on A.Id = B.ID
JOIN C on A.id = B.ID
WHERE (SELECT MAX(COUNT)
FROM A
WHERE Id = <what goes here????>)
To summarise, what I want is Values from Table B, FileNumber from Table c (where the count is Max for ID from table A).
UPDATE: COrrecting table C above. Looks like I need Table A.
I think this is the query you're looking for:
select b.*, c.filenumber from b
join (
select id, max(count) as count from a
group by id
) as NewA on b.id = NewA.id
join c on NewA.count = c.count
However, you should take into account that I don't get why for id=1 in tableA you choose the 16 to match against table C (which is the max) and for id=2 in tableA you choose the 10 to match against table C (which is the min). I assumed you meant the max in both cases.
Edit:
I see you've updated tableA data. The query results in this, given the previous data:
+----+---------------+------------+
| ID | FILENAME | FILENUMBER |
+----+---------------+------------+
| 1 | sample1.file | 1234 |
| 2 | sample2.file | 3456 |
| 3 | sample3.file | 4567 |
+----+---------------+------------+
Here is a working example
Using Mosty’s working example (renaming the keyword count to cnt for a column name), this is another approach:
with abc as (
select
a.id,
a.cnt,
rank() over (
partition by a.id
order by cnt desc
) as rk,
b.filename
from a join b on a.id = b.id
)
select
abc.id, abc.filename, c.filenumber
from abc join c
on c.cnt = abc.cnt
where rk = 1;
select
PreMax.ID,
B.FileName,
C2.FileNumber
from
( select C.id, max( C.count ) maxPerID
from TableC C
group by C.ID
order by C.ID ) PreMax
JOIN TableC C2
on PreMax.ID = C2.ID
AND PreMax.maxPerID = C2.Count
JOIN TableB B
on PreMax.ID = B.ID
Given this data on SQL Server 2005:
SectionID Name
1 Dan
2 Dan
4 Dan
5 Dan
2 Tom
7 Tom
9 Tom
10 Tom
How would I select records where the sectionID must be +-2 or more from another section for the same name.
The result would be:
1 Dan
4 Dan
2 Tom
7 Tom
9 Tom
Thanks for reading!
SELECT *
FROM mytable a
WHERE NOT EXISTS
(SELECT *
FROM mytable b
WHERE a.Name = b.Name
AND a.SectionID = b.SectionID + 1)
Here's LEFT JOIN variant of Anthony's answer (removes consecutive id's from the results)
SELECT a.*
FROM mytable a
LEFT JOIN mytable b ON a.Name = b.Name AND a.SectionID = b.SectionID + 1
WHERE b.SectionID IS NULL
EDIT: Since there is another interpretation of the question (simply getting results where id's are more than 1 number apart) here is another attempt at an answer:
WITH alternate AS (
SELECT sectionid,
name,
EXISTS(SELECT a.sectionid
FROM mytable b
WHERE a.name = b.name AND
(a.sectionid = b.sectionid-1 or a.sectionid = b.sectionid+1)) as has_neighbour,
row_number() OVER (PARTITION by a.name ORDER BY a.name, a.sectionid) as row_no
FROM mytable a
)
SELECT sectionid, name
FROM alternate
WHERE row_no % 2 = 1 OR NOT(has_neighbour)
ORDER BY name, sectionid;
gives:
sectionid | name
-----------+------
1 | Dan
4 | Dan
2 | Tom
7 | Tom
9 | Tom
Logic: if a record has neighbors with same name and id+/-1 then every odd row is taken, if it has no such neighbors then it gets the row regardless if it is even or odd.
As stated in the comment the condition is ambiguous - on start of each new sequence you might start with odd or even rows and the criteria will still be satisfied with different results (even with different number of results).