SQL Group by colum1 "keep" by datetime - sql

I have the follow table:
ID -- timestamps -- uid
1 -- 12:00 -- 1
2 -- 12:15 -- 1
3 -- 12:30 -- 2
4 -- 12:45 -- 2
Now I need unique uid's by the last timestamps, result have to look like this:
ID -- timestamps -- uid
2 -- 12:15 -- 1
4 -- 12:45 -- 2
If there is any problem with joins, tell me please.
Thats my current SQL Statmant:
SELECT DISTINCT "lists".* FROM "lists" INNER JOIN identifys i WHERE (i.ip
= '1' OR i.session = '2')
And that my ActiveRecord:
List.all.joins("INNER JOIN identifys i")
.where("i.ip = ? OR i.session = ?", ip, session)
.distinct

How about adding Group by to your query? Something along these lines:
select Max(l.ID) as ID, Max(l.timestamps) as timestamps, l.uid
from Lists l INNER JOIN identifys i
WHERE (i.ip = '1' OR i.session = '2')
Group By l.uid
Another possible solution:
SELECT l2.id , a.uid, a.timestamps
FROM
(
SELECT Max(l.timestamps) as timestamps, l.uid
FROM Lists l INNER JOIN identifys i
WHERE (i.ip = '1' OR i.session = '2')
Group By l.uid
) a
Inner Join Lists l2 on a.timestamps = l2.timestamps

In MySQL or SQLite you could use a filtering join, like:
select *
from YourTable yt
join (
select UID
, max(timestamp) as max_timestamp
from YourTable
group by
UID
) filter
on yt.UID = filter.UID
and yt.timestamp = filter.max_timestamp
In a datase that supports windowing functions, like PostgreSQL, Oracle or SQL Server, you could:
select *
from (
select row_number() (
partition by UID
order by timestamp desc) as rn
, *
from YourTable
) SubQueryAlias
where rn = 1 -- Only latest row per UID

Related

Get result where exist on date X and not exist on day Y

I have a table where I store some info about events. My table have columns: id, created_at(which is date field), key(which is varchar255), quantity(which is integer) and event(which is varchar255). I'm making query to take all keys which exists on date X (for example 2022-09-05) and NOT exists on date Y (example 2022-09-06). The table has no relation with other tables.
The query that I tried is:
SELECT s.key
FROM stats s
WHERE created_at = '2022-09-05'
AND NOT EXISTS(
SELECT *
FROM stats s
WHERE s.created_at = '2022-09-06'
)
GROUP BY s.key
;
The problem is this returns me 0 result, but I expect at least 1.
You have to check that the key of 2022-09-05 does not appear on 2022-09-06. So the query changes to
SELECT s.key
FROM stats s
WHERE s.created_at = '2022-09-05' AND NOT EXISTS
(SELECT FROM stats st WHERE st.key = s.key AND st.created_at = '2022-09-06');
You can try this
SELECT s.key
FROM stats s
LEFT JOIN (
SELECT s.key FROM stats s
WHERE created_at = '2022-09-05'
) dayAfter ON s.key = dayAfter.key
WHERE s.created_at = '2022-09-06'
AND dayAfter.key IS NULL
GROUP BY s.key

Left join statement has no column 'client'

I am trying to append a column to the right
SELECT
'abc' as client,
sum(nested.freq) as freq,
FROM
(
SELECT
uh.route
COUNT(uh.route) as freq
FROM
employee AS up,
hist AS uh
where
up.id = uh.eID
AND uh.PrhEEBankRoute = '123'
GROUP BY
uh.route
) AS nested
LEFT JOIN (
SELECT
'abc' as client,
sum(raw.freq) as total_trans
FROM
(
SELECT
uh.route,
COUNT(uh.route) as freq
FROM
employee AS up,
hist AS uh
where
up.id = uh.eID
GROUP BY
uh.route
) AS raw
) raw2 ON raw2.client = nested.client;
The expected result is something like this
client | freq | total_trans
abc | 2 | 100
But I am getting the following error:
left join statement has no column 'client'
The first subquery, aliased as "nested" is:
SELECT
uh.route --<< no column called "client"
, COUNT(uh.route) AS freq --<< no column called "client"
FROM employee AS up
, hist AS uh
WHERE up.id = uh.eID
AND uh.PrhEEBankRoute = '123'
GROUP BY uh.route
In the next subquery at the join condition you refer to nested.client
) raw2 ON raw2.client = nested.client;
That column does not exist in the nested subquery, so the error message is accurate.

How To use Where instead of Group by?

I wrote a query , that gives me this Output :
(This is Just a sample obviously the Output Table contains 300000 rows approximatly)
And This is my Query :
proc sql;
create Table Output as
select ID_User, Division_ID, sum(conta) as Tot_Items, max(Counts) as Max_Item
from (select c.ID_User , c.Div_ID as Division_ID, ro.code as Mat, count(*) as Counts
from Ods.R_Ordini o
inner join DMC.Cust_Dupl c
on User_ID = ID_User
inner join ods.R_Nlines ro
on ro.Orders_Id = o.Id_Orders AND RO.SERVICE = 0
inner join ods.R_Mat m
on ro.Mat_Id = Id_Mat and flag = 0
group by
ID_User,
C.Division_ID,
Ro.Code
Having Counts > 1
)
group by
Id_User,
Division_ID
Order by
Tot_Item DESC
;
quit;
So , What i want is to re-write this Query , but instead of the Group by i want to use the Where Condition , (WHERE=(DIVISION_ID=3)) this is the condition.
I tried several attempts , with some i got errors , and with others i did got an output , but the output was not like the original one.
any help would be much appreciated , thank you.
The SAS data set option (where=(<where-expression>)) can only be coded adjacent to a data set name. So the option would have to be applied to the data set containing the column div_id that is the basis for computed column division_id. That would be table alias c
DMC.Cust_Dupl(where=(div_id=3)) as c
Or just use a normal SQL where clause
…
)
where division_id=3
group by …
Just use WHERE DIVISION_ID=3 before group by.
select ID_User, Division_ID, sum(conta) as Tot_Items, max(Counts) as Max_Item from (select c.ID_User , c.Div_ID as Division_ID, ro.code as Mat, count(*) as Counts from Ods.R_Ordini o inner join DMC.Cust_Dupl c on User_ID = ID_User inner join ods.R_Nlines ro on ro.Orders_Id = o.Id_Orders AND RO.SERVICE = 0 inner join ods.R_Mat m on ro.Mat_Id = Id_Mat and flag = 0 WHERE DIVISION_ID=3 group by ID_User, C.Division_ID, Ro.Code Having Counts > 1 ) group by Id_User, Division_ID Order by Tot_Item DESC

Limit join to one row

I have the following query:
SELECT sum((select count(*) as itemCount) * "SalesOrderItems"."price") as amount, 'rma' as
"creditType", "Clients"."company" as "client", "Clients".id as "ClientId", "Rmas".*
FROM "Rmas" JOIN "EsnsRmas" on("EsnsRmas"."RmaId" = "Rmas"."id")
JOIN "Esns" on ("Esns".id = "EsnsRmas"."EsnId")
JOIN "EsnsSalesOrderItems" on("EsnsSalesOrderItems"."EsnId" = "Esns"."id" )
JOIN "SalesOrderItems" on("SalesOrderItems"."id" = "EsnsSalesOrderItems"."SalesOrderItemId")
JOIN "Clients" on("Clients"."id" = "Rmas"."ClientId" )
WHERE "Rmas"."credited"=false AND "Rmas"."verifyStatus" IS NOT null
GROUP BY "Clients".id, "Rmas".id;
The problem is that the table "EsnsSalesOrderItems" can have the same EsnId in different entries. I want to restrict the query to only pull the last entry in "EsnsSalesOrderItems" that has the same "EsnId".
By "last" entry I mean the following:
The one that appears last in the table "EsnsSalesOrderItems". So for example if "EsnsSalesOrderItems" has two entries with "EsnId" = 6 and "createdAt" = '2012-06-19' and '2012-07-19' respectively it should only give me the entry from '2012-07-19'.
SELECT (count(*) * sum(s."price")) AS amount
, 'rma' AS "creditType"
, c."company" AS "client"
, c.id AS "ClientId"
, r.*
FROM "Rmas" r
JOIN "EsnsRmas" er ON er."RmaId" = r."id"
JOIN "Esns" e ON e.id = er."EsnId"
JOIN (
SELECT DISTINCT ON ("EsnId") *
FROM "EsnsSalesOrderItems"
ORDER BY "EsnId", "createdAt" DESC
) es ON es."EsnId" = e."id"
JOIN "SalesOrderItems" s ON s."id" = es."SalesOrderItemId"
JOIN "Clients" c ON c."id" = r."ClientId"
WHERE r."credited" = FALSE
AND r."verifyStatus" IS NOT NULL
GROUP BY c.id, r.id;
Your query in the question has an illegal aggregate over another aggregate:
sum((select count(*) as itemCount) * "SalesOrderItems"."price") as amount
Simplified and converted to legal syntax:
(count(*) * sum(s."price")) AS amount
But do you really want to multiply with the count per group?
I retrieve the the single row per group in "EsnsSalesOrderItems" with DISTINCT ON. Detailed explanation:
Select first row in each GROUP BY group?
I also added table aliases and formatting to make the query easier to parse for human eyes. If you could avoid camel case you could get rid of all the double quotes clouding the view.
Something like:
join (
select "EsnId",
row_number() over (partition by "EsnId" order by "createdAt" desc) as rn
from "EsnsSalesOrderItems"
) t ON t."EsnId" = "Esns"."id" and rn = 1
this will select the latest "EsnId" from "EsnsSalesOrderItems" based on the column creation_date. As you didn't post the structure of your tables, I had to "invent" a column name. You can use any column that allows you to define an order on the rows that suits you.
But remember the concept of the "last row" is only valid if you specifiy an order or the rows. A table as such is not ordered, nor is the result of a query unless you specify an order by
Necromancing because the answers are outdated.
Take advantage of the LATERAL keyword introduced in PG 9.3
left | right | inner JOIN LATERAL
I'll explain with an example:
Assuming you have a table "Contacts".
Now contacts have organisational units.
They can have one OU at a point in time, but N OUs at N points in time.
Now, if you have to query contacts and OU in a time period (not a reporting date, but a date range), you could N-fold increase the record count if you just did a left join.
So, to display the OU, you need to just join the first OU for each contact (where what shall be first is an arbitrary criterion - when taking the last value, for example, that is just another way of saying the first value when sorted by descending date order).
In SQL-server, you would use cross-apply (or rather OUTER APPLY since we need a left join), which will invoke a table-valued function on each row it has to join.
SELECT * FROM T_Contacts
--LEFT JOIN T_MAP_Contacts_Ref_OrganisationalUnit ON MAP_CTCOU_CT_UID = T_Contacts.CT_UID AND MAP_CTCOU_SoftDeleteStatus = 1
--WHERE T_MAP_Contacts_Ref_OrganisationalUnit.MAP_CTCOU_UID IS NULL -- 989
-- CROSS APPLY -- = INNER JOIN
OUTER APPLY -- = LEFT JOIN
(
SELECT TOP 1
--MAP_CTCOU_UID
MAP_CTCOU_CT_UID
,MAP_CTCOU_COU_UID
,MAP_CTCOU_DateFrom
,MAP_CTCOU_DateTo
FROM T_MAP_Contacts_Ref_OrganisationalUnit
WHERE MAP_CTCOU_SoftDeleteStatus = 1
AND MAP_CTCOU_CT_UID = T_Contacts.CT_UID
/*
AND
(
(#in_DateFrom <= T_MAP_Contacts_Ref_OrganisationalUnit.MAP_KTKOE_DateTo)
AND
(#in_DateTo >= T_MAP_Contacts_Ref_OrganisationalUnit.MAP_KTKOE_DateFrom)
)
*/
ORDER BY MAP_CTCOU_DateFrom
) AS FirstOE
In PostgreSQL, starting from version 9.3, you can do that, too - just use the LATERAL keyword to achieve the same:
SELECT * FROM T_Contacts
--LEFT JOIN T_MAP_Contacts_Ref_OrganisationalUnit ON MAP_CTCOU_CT_UID = T_Contacts.CT_UID AND MAP_CTCOU_SoftDeleteStatus = 1
--WHERE T_MAP_Contacts_Ref_OrganisationalUnit.MAP_CTCOU_UID IS NULL -- 989
LEFT JOIN LATERAL
(
SELECT
--MAP_CTCOU_UID
MAP_CTCOU_CT_UID
,MAP_CTCOU_COU_UID
,MAP_CTCOU_DateFrom
,MAP_CTCOU_DateTo
FROM T_MAP_Contacts_Ref_OrganisationalUnit
WHERE MAP_CTCOU_SoftDeleteStatus = 1
AND MAP_CTCOU_CT_UID = T_Contacts.CT_UID
/*
AND
(
(__in_DateFrom <= T_MAP_Contacts_Ref_OrganisationalUnit.MAP_KTKOE_DateTo)
AND
(__in_DateTo >= T_MAP_Contacts_Ref_OrganisationalUnit.MAP_KTKOE_DateFrom)
)
*/
ORDER BY MAP_CTCOU_DateFrom
LIMIT 1
) AS FirstOE
Try using a subquery in your ON clause. An abstract example:
SELECT
*
FROM table1
JOIN table2 ON table2.id = (
SELECT id FROM table2 WHERE table2.table1_id = table1.id LIMIT 1
)
WHERE
...

Multiple MAX values select using inner join

I have query that work for me only when values in the StakeValue don't repeat.
Basically, I need to select maximum values from SI_STAKES table with their relations from two other tables grouped by internal type.
SELECT a.StakeValue, b.[StakeName], c.[ProviderName]
FROM SI_STAKES AS a
INNER JOIN SI_STAKESTYPES AS b ON a.[StakeTypeID] = b.[ID]
INNER JOIN SI_PROVIDERS AS c ON a.[ProviderID] = c.[ID] WHERE a.[EventID]=6
AND a.[StakeGroupTypeID]=1
AND a.StakeValue IN
(SELECT MAX(d.StakeValue) FROM SI_STAKES AS d
WHERE d.[EventID]=a.[EventID] AND d.[StakeGroupTypeID]=a.[StakeGroupTypeID]
GROUP BY d.[StakeTypeID])
ORDER BY b.[StakeName], a.[StakeValue] DESC
Results for example must be:
[ID] [MaxValue] [StakeTypeID] [ProviderName]
1 1,5 6 provider1
2 3,75 7 provider2
3 7,6 8 provider3
Thank you for your help
There are two problems to solve here.
1) Finding the max values per type. This will get the Max value per StakeType and make sure that we do the exercise only for the wanted events and group type.
SELECT StakeGroupTypeID, EventID, StakeTypeID, MAX(StakeValue) AS MaxStakeValue
FROM SI_STAKES
WHERE Stake.[EventID]=6
AND Stake.[StakeGroupTypeID]=1
GROUP BY StakeGroupTypeID, EventID, StakeTypeID
2) Then we need to get only one return back for that value since it may be present more then once.
Using the Max Value, we must find a unique row for each I usually do this by getting the Max ID is has the added advantage of getting me the most recent entry.
SELECT MAX(SMaxID.ID) AS ID
FROM SI_STAKES AS SMaxID
INNER JOIN (
SELECT StakeGroupTypeID, EventID, StakeTypeID, MAX(StakeValue) AS MaxStakeValue
FROM SI_STAKES
WHERE Stake.[EventID]=6
AND Stake.[StakeGroupTypeID]=1
GROUP BY StakeGroupTypeID, EventID, StakeTypeID
) AS SMaxVal ON SMaxID.StakeTypeID = SMaxVal.StakeTypeID
AND SMaxID.StakeValue = SMaxVal.MaxStakeValue
AND SMaxID.EventID = SMaxVal.EventID
AND SMaxID.StakeGroupTypeID = SMaxVal.StakeGroupTypeID
3) Now that we have the ID's of the rows that we want, we can just get that information.
SELECT Stakes.ID, Stakes.StakeValue, SType.StakeName, SProv.ProviderName
FROM SI_STAKES AS Stakes
INNER JOIN SI_STAKESTYPES AS SType ON Stake.[StakeTypeID] = SType.[ID]
INNER JOIN SI_PROVIDERS AS SProv ON Stake.[ProviderID] = SProv.[ID]
WHERE Stake.ID IN (
SELECT MAX(SMaxID.ID) AS ID
FROM SI_STAKES AS SMaxID
INNER JOIN (
SELECT StakeGroupTypeID, EventID, StakeTypeID, MAX(StakeValue) AS MaxStakeValue
FROM SI_STAKES
WHERE Stake.[EventID]=6
AND Stake.[StakeGroupTypeID]=1
GROUP BY StakeGroupTypeID, EventID, StakeTypeID
) AS SMaxVal ON SMaxID.StakeTypeID = SMaxVal.StakeTypeID
AND SMaxID.StakeValue = SMaxVal.MaxStakeValue
AND SMaxID.EventID = SMaxVal.EventID
AND SMaxID.StakeGroupTypeID = SMaxVal.StakeGroupTypeID
)
You can use the over clause since you're using T-SQL (hopefully 2005+):
select distinct
a.stakevalue,
max(a.stakevalue) over (partition by a.staketypeid) as maxvalue,
b.staketypeid,
c.providername
from
si_stakes a
inner join si_stakestypes b on
a.staketypeid = b.id
inner join si_providers c on
a.providerid = c.id
where
a.eventid = 6
and a.stakegrouptypeid = 1
Essentially, this will find the max a.stakevalue for each a.staketypeid. Using a distinct will return one and only one row. Now, if you wanted to include the min a.id along with it, you could use row_number to accomplish this:
select
s.id,
s.maxvalue,
s.staketypeid,
s.providername
from (
select
row_number() over (order by a.stakevalue desc
partition by a.staketypeid) as rownum,
a.id,
a.stakevalue as maxvalue,
b.staketypeid,
c.providername
from
si_stakes a
inner join si_stakestypes b on
a.staketypeid = b.id
inner join si_providers c on
a.providerid = c.id
where
a.eventid = 6
and a.stakegrouptypeid = 1
) s
where
s.rownum = 1