I have values
- id|type|Status|Comment
- 1 | P | 1 | AAA
- 2 | P | 2 | BBB
- 3 | P | 3 | CCC
- 4 | S | 1 | DDD
- 5 | S | 2 | EEE
I wan to get values for each type with max status and with comment from the row with max status:
- id|type|Status|Comment
- 3 | P | 3 | CCC
- 5 | S | 2 | EEE
All the existing questions on SO do not care about the right correspondence of Max type and value.
This gives you one row per type, which have max status
select * from (
select your_table.*, row_number() over(partition by type order by Status desc) as rn from your_table
) tt
where rn = 1
Corrected: The below will use a subquery to figure out each type and what the max status is, then it joins that onto the original table and uses the where clause to only select those rows where the status equals the max status. Of note, if you have multiple records with the same max status, you will get both of them to come up.
WITH T1 AS (SELECT type, MAX(STATUS) AS max_status FROM table_name GROUP BY type)
SELECT t2.id, t2.type, t2.status, t2.comment
FROM T1 LEFT JOIN table_name t2 ON t2.type= T1.type
WHERE t2.status = T1.max_status
Related
I've got myself in a bit of a mess on something I'm doing where I'm trying to get two tables linked together based on multiple bits of info.
I want to link one table to another based on the basic rules of(in this hierarchy)
where main linking is where orderid matches between the two tables
records from table 2 where valid=Y,
from those i want the valid records which has the highest seqn1 number and then from those the one that has the highest seqn2 value
table1
orderid | date | otherinfo
223344 | 22/10/2020 | okokkokokooeodijjf
table2
orderid | seqn1 | seqn2 | valid | additonaldata
223344 | 1 | 3 | y | sdfsfsf
223344 | 2 | 1 | y | sffferfr
223344 | 2 | 2 | y | sfrfrefr -- This row
223344 | 2 | 3 | n | rfrg66rr
223344 | 2 | 4 | n | adwere
223344 | 3 | 4 | n | adwere
so would want the final record to be
orderid | date | otherinfo | seqn1 | seqn2 | valid | additonaldata
223344 | 22/10/2020 | okokkokokooeodijjf | 2 | 2 | y | sfrfrefr
I started off with the code below but I'm not sure I'm doing it right and I can't seem to get it to pay attention to the valid flag when i try to add it in.
SELECT * FROM table1
left JOIN table2
ON table1.orderid = table2.orderid
AND table2.seqn1 = (SELECT MAX(table2.seqn1) FROM table2 WHERE table1.orderid = table2.orderid)
AND table2.seqn2 = (SELECT MAX(table2.seqn2) FROM table2 WHERE table1.orderid = table2.orderid
AND table2.seqn1 = (SELECT MAX(table2.seqn1) FROM table2 WHERE table1.orderid = table2.orderid))
Could someone help me amend the code please.
Use row_number analytic function with partition by orderid and order by SEQNRs in the order you need. No need for multiple subselects. To add more selections for the single row, use CASE to map your values to numbers and order by them also.
Fiddle here.
with l as (
select *,
rank() over(partition by orderid order by seqn1 desc, seqn2 desc) as rn
from line
where valid = 'y'
)
select *
from header as h
join l
on h.orderid = l.orderid
and l.rn = 1
How about something like this:
;
with cte_table2 as
(
SELECT ordered
,MAX(seqn1) as seqn1
,MAX(seqn2) as seqn2
FROM table2
where valid = 'y'
group by ordered --check if you need to add 'valid' to the group by but I don't think so.
)
SELECT
t1.*
,t3.otherinfo
--,t3.[OtherFields]
from table1 t1
inner join cte_table2 t2 on t1.orderid = t2.orderid -- first match on id
left join table2 t3 on t3.orderid = t2.orderid and t3.seqn1 = t2.seqn1 and t3.seqn2 = t2.seqn2
Let's say we have 2 tables:
Table1: Table2:
id | t2id id | col
---------- ----------
1 | 1 1 | a
2 | 2 2 | b
3 | 2 3 | c
4 | 1 4 | d
5 | 3 5 | e
6 | 3 6 | f
7 | 4 7 | g
8 | 5 8 | h
9 | 1 9 | i
10 | 4 10 | j
My question is:
Is there any short way to put limit for distinct results of Table1.t2id column?
For example: if limit = 2 then all rows with t2id from 1 to 2 (or any other values) are selected.
Expected result (with limit = 2):
Res:
id | t2id
----------
1 | 1
2 | 2
3 | 2
4 | 1
9 | 1
Note:
Any information or suggestion are accepted
You could use just the where clause
Select id,t2id
from table1
where t2id<=2
Or you can use where .. between
Select id,t2id
from table1
where t2id between 1 and 2
I believe you want to:
Create a subquery with all the columns you need + this one: DENSE_RANK() OVER (ORDER BY Table1.t2id) AS MyRank
outside of the sub-query, add a where on MyRank
Complete solution:
SELECT id, tb2id
FROM (
SELECT id, tb2id, DENSE_RANK() OVER (ORDER BY Table1.t2id) AS MyRank
FROM table1
) MySubQuery
WHERE MyRank <= 2
This will adapt to JOINs with table2 (with potential multiplicity increase) and non-consecutive values in tb2id.
You can also use in:
select t1.*
from table1 t1
where t1.t2_id in (select t2.id from table2 t2 limit 2);
The advantage of this approach is that it is easy to make it random:
select t1.*
from table1 t1
where t1.t2_id in (select t2.id from table2 t2 order by random() limit 2);
I have table (t_image) with this column
datacd | imagecode | indexdate
----------------------------------
A | 1 | 20170213
A | 2 | 20170213
A | 3 | 20170214
B | 4 | 20170201
B | 5 | 20170202
desired result is this
datacd | imagecode | indexdate
----------------------------------
A | 1 | 20170213
B | 4 | 20170201
In the above table, I want to retrieve 1 row for each datacd who has the minimum index date
Here is my query, but the result returns 2 rows for datacd A
select *
from (
select datacd, min(indexdate) as indexdate
from t_image
group by datacd
) as t1 inner join t_image as t2 on t2.datacd = t1.datacd and t2.indexdate = t1.indexdate;
The Postgres proprietary distinct on () operator is typically the fastest solution for greatest-n-per-group queries:
select distinct on (datacd) *
from t_image
order by datacd, indexdate;
One option uses ROW_NUMBER():
SELECT t.datacd,
t.imagecode,
t.indexdate
FROM
(
SELECT datacd, imagecode, indexdate,
ROW_NUMBER() OVER (PARTITION BY datacd ORDER BY indexdate) rn
FROM t_image
) t
WHERE t.rn = 1
I want to create a view in my database, based on these three tables:
I would like to select the rows in table3 that has the highest value in Weight, for rows that has the same value in Count.
Then I want them grouped by Category_ID and ordered by Date, so that if two rows in table3 are identical, I want the newest.
Let me give you an example:
Table1
ID | Date | UserId
1 | 2015-01-01 | 1
2 | 2015-01-02 | 1
Table2
ID | table1_ID | Category_ID
1 | 1 | 1
2 | 2 | 1
Table3
ID | table2_ID | Count | Weight
1 | 1 | 5 | 10
2 | 1 | 5 | 20 <-- count is 5 and weight is highest
3 | 1 | 3 | 40
4 | 2 | 5 | 10
5 | 2 | 3 | 40 <-- newest of the two equal rows
Then the result should be row 2 and 5 from table 3.
PS I'm doing this in mssql.
PPS I'm sory if the title is not appropriate, but I did not know how to formulate a good one.
SELECT
*
FROM
(
SELECT
t3.*
,RANK() OVER (PARTITION BY [Count] ORDER BY [Weight] DESC, Date DESC) highest
FROM TABLE3 t3
INNER JOIN TABLE2 t2 ON t2.Id = t3.Table2_Id
INNER JOIN TABLE1 t1 ON t1.Id = t2.Table1_Id
) t
WHERE t.Highest = 1
This will group by the Count (which must be the same). Then it will determine which has the highest weight. If two of more of them have the same 'heighest' weight, it takes the one with the most recent date first.
You can use RANK() analytic function here, and give those rows a rank and than choose the first rank for each ID
Something like
select *
from
(select
ID, table2_ID, Count, Weight,
RANK() OVER (PARTITION BY ID ORDER BY Count, Weight DESC) as Highest
from table3)
where Highest = 1;
This is the syntax for Oracle, if you not using it look in the internet for the your syntax which should be almost the same
I'm trying to group data in sequence order. Say I have the following table:
| 1 | A |
| 1 | A |
| 1 | B |
| 1 | B |
| 1 | C |
| 1 | B |
I need the SQL query to output the following:
| 1 | A | 1 |
| 1 | A | 1 |
| 1 | B | 2 |
| 1 | B | 2 |
| 1 | C | 3 |
| 1 | B | 4 |
The last column is a group number that is incremented in each group. The important thing to note is that rows 3, 4 and 5 contain the same data which should be grouped into 2 groups not 1.
For MSSQL2008:
Suppose you have a SampleStatuses table:
Status Date
A 2014-06-11
A 2014-06-14
B 2014-06-25
B 2014-07-01
A 2014-07-06
A 2014-07-19
B 2014-07-21
B 2014-08-13
C 2014-08-19
you write the following:
;with
cte as (
select top 1 RowNumber, 1 as GroupNumber, [Status], [Date] from SampleStatuses order by RowNumber
union all
select c1.RowNumber,
case when c2.Status <> c1.Status then c2.GroupNumber + 1 else c2.GroupNumber end as GroupNumber, c1.[Status], c1.[Date]
from cte c2 join SampleStatuses c1 on c1.RowNumber = c2.RowNumber + 1
)
select * from cte;
you get this result:
RowNumber GroupNumber Status Date
1 1 A 2014-06-11
2 1 A 2014-06-14
3 2 B 2014-06-25
4 2 B 2014-07-01
5 3 A 2014-07-06
6 3 A 2014-07-19
7 4 B 2014-07-21
8 4 B 2014-08-13
9 5 C 2014-08-19
The normal way you would do what you want is the dense_rank function:
select key, val,
dense_rank() over (order by key, val)
from t
However, this does not address the problem of separating the last groups.
To handle this, I have to assume there is an "id" column. Tables, in SQL, do not have an ordering, so I need the ordering. If you are using SQL Server 2012, then you can use the lag() function to get what you need. Use the lag to see if the key, val pair is the same on consecutive rows:
with t1 as (
select id, key, val,
(case when key = lead(key, 1) over (order by id) and
val = lead(val, 1) over (order by id)
then 1
else 0
end) as SameAsNext
from t
)
select id, key, val,
sum(SameAsNext) over (order by id) as GroupNum
from t
Without SQL Server 2012 (which has cumulative sums), you have to do a self-join to identify the beginning of each group:
select t.*,
from t left outer join
t tprev
on t.id = t2.id + 1 and t.key = t2.key and t.val = t2.val
where t2.id is null
With this, assign the group as the minimum id using a join:
select t.id, t.key, t.val,
min(tgrp.id) as GroupId
from t left outer join
(select t.*,
from t left outer join
t tprev
on t.id = t2.id + 1 and t.key = t2.key and t.val = t2.val
where t2.id is null
) tgrp
on t.id >= tgrp.id
If you want these to be consecutive numbers, then put them in a subquery and use dense_rank().
This will give you rankings on your columns.
It will not give you 1,2,3 however.
It will give you 1,3,6 etc based on how many in each grouping
select
a,
b,
rank() over (order by a,b)
from
table1
See this SQLFiddle for a clearer idea of what I mean: http://sqlfiddle.com/#!3/0f201/2/0