I am trying to write a query which uses a list of unique LOCATIONs obtained from a first query, as criteria to query rows from a second table.
For example:
SELECT
TABLE_A."LOCATION",
MIN(TABLE_A.WORKDATE) AS MIN_WORK_DATE
FROM
DB.TABLE_A
WHERE
MIN_WORK_DATE > '201201'
Then somehow:
SELECT
TABLE_B."LOCATION",
(other fields of interest)
FROM
DB.TABLE_B
WHERE
TABLE_B."LOCATION" (is contained in the result above)
Thanks in advance for any help!
You can do it with join:
SELECT
b.location,
(other fields of interest)
FROM
tableB b
JOIN
(SELECT a.location, min(a.workdate) as min_workdate
FROM tableA a
GROUP BY a.location) c
ON b.location = c.location
WHERE c.min_workdate > '201201'
Fiddle
You can match any table's column with any another table's column:
EX:
SELECT
TABLE_A."LOCATION",
TABLE_A.WORKDATE AS WORK_DATE
FROM
DB.TABLE_A, DB.TABLE_B
WHERE
TABLE_A.SOME_COLUMN > 'some_value_given' and TABLE_A.SOME_COLUMN=TABLE_B.SOME_COULMN
Related
I have tables A, B, C. Table A is linked to B, and table A is linked to C. I want to join the 3 tables and find the sum of B.cost and the sum of C.clicks. However, it is not giving me the expected value, and when I select everything without the group by, it is showing duplicate rows. I am expecting the row values from B to roll up into a single sum, and the row values from C to roll up into a single sum.
My query looks like
select A.*, sum(B.cost), sum(C.clicks) from A
join B
left join C
group by A.id
having sum(cost) > 10
I tried to group by B.a_id and C.another_field_in_a also, but that didn't work.
Here is a DB fiddle with all of the data and the full query:
http://sqlfiddle.com/#!9/768745/13
Notice how the sum fields are greater than the sum of the individual tables? I'm expecting the sums to be equal, containing only the rows of the table B and C once. I also tried adding distinct but that didn't help.
I'm using Postgres. (The fiddle is set to MySQL though.) Ultimately I will want to use a having clause to select the rows according to their sums. This query will be for millions of rows.
If I understand the logic correctly, the problem is the Cartesian product caused by the two joins. Your query is a bit hard to follow, but I think the intent is better handled with correlated subqueries:
select k.*,
(select sum(cost)
from ad_group_keyword_network n
where n.event_date >= '2015-12-27' and
n.ad_group_keyword_id = 1210802 and
k.id = n.ad_group_keyword_id
) as cost,
(select sum(clicks)
from keyword_click c
where (c.date is null or c.date >= '2015-12-27') and
k.keyword_id = c.keyword_id
) as clicks
from ad_group_keyword k
where k.status = 2 ;
Here is the corresponding SQL Fiddle.
EDIT:
The subselect should be faster than the group by on the unaggregated data. However, you need the right indexes: ad_group_keyword_network(ad_group_keyword_id, ad_group_keyword_id, event_date, cost) and keyword_click(keyword_id, date, clicks).
I found this (MySQL joining tables group by sum issue) and created a query like this
select *
from A
join (select B.a_id, sum(B.cost) as cost
from B
group by B.a_id) B on A.id = B.a_id
left join (select C.keyword_id, sum(C.clicks) as clicks
from C
group by C.keyword_id) C on A.keyword_id = C.keyword_id
group by A.id
having sum(cost) > 10
I don't know if it's efficient though. I don't know if it's more or less efficient than Gordon's. I ran both queries and this one seemed faster, 27s vs. 2m35s. Here is a fiddle: http://sqlfiddle.com/#!15/c61c74/10
Simply split the aggregate of the second table into a subquery as follows:
http://sqlfiddle.com/#!9/768745/27
select ad_group_keyword.*, SumCost, sum(keyword_click.clicks)
from ad_group_keyword
left join keyword_click on ad_group_keyword.keyword_id = keyword_click.keyword_id
left join (select ad_group_keyword.id, sum(cost) SumCost
from ad_group_keyword join ad_group_keyword_network on ad_group_keyword.id = ad_group_keyword_network.ad_group_keyword_id
where event_date >= '2015-12-27'
group by ad_group_keyword.id
having sum(cost) > 20
) Cost on Cost.id=ad_group_keyword.id
where
(keyword_click.date is null or keyword_click.date >= '2015-12-27')
and status = 2
group by ad_group_keyword.id
table a.
Table b . I have two tables. Table A has over 8000+ records and continues to grow with time.
Table B has only 5 or so records and grows rarely but does grow sometimes.
I want to query Table A's last records where the Id for Table A matches for Table B. The problem is; I am getting all the rows from Table A. I just need the ones where Table A and B match once. These are unique Id's when a new row is inserted into table B and never get repeated.
Any help is most appreciated.
SELECT a.nshift,
a.loeeworkcellid,
b.loeeconfigworkcellid,
b.loeescheduleid,
b.sdescription,
b.sshortname
FROM oeeworkcell a
INNER JOIN dbo.oeeconfigworkcell b
ON a.loeeconfigworkcellid = b.loeeconfigworkcellid
ORDER BY a.loeeworkcellid DESC
I am assuming you want to get the only the lastest (as you said) row from the TableA but JOIN giving you all the rows.You can use the Row_Number() to get the rownumber and then apply the join and filter it with the Where clause to select only the first row from the JOIN. So what you can try as below,
;WITH CTE
AS
(
SELECT * , ROW_NUMBER() OVER(PARTITION BY loeeconfigworkcellid ORDER BY loeeworkcellid desc) AS Rn
FROM oeeworkcell
)
SELECT a.nshift,
a.loeeworkcellid,
b.loeecoonfigworkcellid,
b.loeescheduleid,
b.sdescription,
b.sshortname
FROM CTE a
INNER JOIN dbo.oeeconfigworkcell b
ON a.loeeconfigworkcellid = b.loeeconfigworkcellid
WHERE
a.Rn = 1
You need to group by your data and select only the data having the condition with min id.
SELECT a.nshift,
a.loeeworkcellid,
b.loeecoonfigworkcellid,
b.loeescheduleid,
b.sdescription,
b.sshortname
FROM oeeworkcell a
INNER JOIN dbo.oeeconfigworkcell b
ON a.loeeconfigworkcellid = b.loeeconfigworkcellid
group by
a.nshift,
a.loeeworkcellid,
b.loeecoonfigworkcellid,
b.loeescheduleid,
b.sdescription,
b.sshortname
having a.loeeworkcellid = min(a.loeeworkcellid)
I have two tables which I need to query. Let's call them table A, and table A_HISTORIES.
Each row from Table A, is linked to multiple rows in A_HISTORIES. What I want to do is to be able to link each row from table A with its earliest history from table A_HISTORIES so something like:-
SELECT A.*
A_HISTORIES.CREATED_DATE
FROM A, A_HISTORIES
WHERE A.ID = A_HISTORIES.A_ID
AND A_HISTORIES.ID = (SELECT max(id) keep (dense_rank first order by CREATED_DATE)
FROM A_HISTORIES)
However, this will only return the row from A/A_HISTORIES that has the earliest CREATED_DATE. Can anyone help me do this per row in A?
Thanks
How about something like this:
SELECT A.*
A_HISTORIES.CREATED_DATE
FROM A
INNER JOIN A_HISTORIES ON A.ID = A_HISTORIES.A_ID
INNER JOIN (SELECT A_ID, MAX(CREATE_DATE) AS max_create_date
FROM A_HISTORIES
GROUP BY A_ID) max_hist ON A_HISTORIES.A_ID = max_hist.A_ID
AND A_HISTORIES.ceate_date = max_create_date
The search term is to ambiguous for google aparently. I am looking at a SQL call and it has 2 FROM keywords? I've never seen this before, can someone explain?
SELECT TOP(5) SUM(column) AS column, column
FROM ( SELECT DISTINCT column, column, column
FROM ((((((table table
INNER JOIN table table ON (column = column
AND column = 2
AND column != '' ))
INNER JOIN table table ON (column = column
AND (column = 144 OR column = 159 OR column = 162 OR column = 164 OR column = 163 OR column = 1 OR column = 2 OR column = 122 OR column = 155 OR column = 156 )))
inner join table table ON (column = column
AND column = 0 ))
INNER JOIN table ON (column = column ))
INNER JOIN table table ON ( column = column
AND (column = 102 OR column = 103 )))
INNER JOIN table table ON (column = column ))) TempTable
GROUP BY column ORDER BY column desc
You will note the multiple FROM keywords. It runs just fine. Just curious to what the purpose is.
This is called as subquery. You can use subquery within your main query
So subquery made the multiple FORM clause.
There's a reason why SQL is called a Structured Query Language: it lets you formulate queries that use other queries as their source, thus creating a hierarchical query structure.
This is a common practice: each FROM keyword is actually paired with its own SELECT, making the inner query a source for the outer one.
Proper formatting would help you understand what is going on: indenting inner SELECTs helps you see the structure of your query, making it easier to understand which part is used as the source of what other parts:
SELECT TOP(5) SUM(price) AS total_price, item_id
FROM ( -- The output of this query serves as input for the outer query
SELECT price, item
FROM order -- This may have its own selects, joins, etc.
GROUP BY order_id
)
GROUP BY item_id
SQL supports SELECTing from the results of another, nested SELECT. As already mentioned, the nested SELECT is called a subquery.
More details about subqueries and examples of their use in MSSQL Server can be found at http://technet.microsoft.com/en-us/library/ms189575(v=sql.105).aspx
Subquery used to select into an aliased column:
USE AdventureWorks2008R2;
GO
SELECT Ord.SalesOrderID, Ord.OrderDate,
(SELECT MAX(OrdDet.UnitPrice)
FROM AdventureWorks.Sales.SalesOrderDetail AS OrdDet
WHERE Ord.SalesOrderID = OrdDet.SalesOrderID) AS MaxUnitPrice
FROM AdventureWorks2008R2.Sales.SalesOrderHeader AS Ord
Using a subquery in the WHERE clause (from http://www.codeproject.com/Articles/200127/SQL-Joins-and-Subqueries)
-- Use a Subquery
SELECT * FROM AdventureWorks.Person.Address
WHERE StateProvinceID IN
(
SELECT StateProvinceID
FROM AdventureWorks.Person.StateProvince
WHERE StateProvinceCode = 'CA'
)
-- Use a Join
SELECT addr.*
FROM AdventureWorks.Person.Address addr
INNER JOIN AdventureWorks.Person.StateProvince state
ON addr.StateProvinceID = state.StateProvinceID
WHERE state.StateProvinceCode = 'CA'
You're seeing FROM clauses in subqueries. If you tabify the query it may be more obvious
SELECT TOP(5) SUM(column) AS column, column
FROM (
SELECT DISTINCT column, column, column
FROM ((((((table table
...
INNER JOIN table table ON (column = column ))) TempTable
GROUP BY column
ORDER BY column desc
I have written below sql for one of the requirement and is fetching my results. But, I am wondering if there is any better way of writing this query rather than using alias table as A.
SELECT A.*,B.OPRDEFNDESC FROM
( select OPRID_ENTERED_BY ,COUNT(*)
from ps_req_hdr
where entered_dt > '01-JUL-2012'
GROUP BY OPRID_ENTERED_BY
ORDER BY COUNT(*) DESC) A, PSOPRDEFN B
WHERE A.OPRID_ENTERED_BY=B.OPRID
You may be able to use a simple INNER JOIN to do the same thing...
SELECT A.OPRID_ENTERED_BY, COUNT(*), B.OPRDEFNDESC
FROM ps_req_hdr A
JOIN PSOPRDEFN B ON A.OPRID_ENTERED_BY = B.OPRID
WHERE A.entered_dt > '01-JUL-2012'
GROUP BY A.OPRID_ENTERED_BY, B.OPRDEFNDESC
ORDER BY COUNT(*) DESC
NOTE
As per the comments below, the COUNT(*) result for this query will NOT include records that don't have corresponding matches in table B, and it will inflate for non-unique matches in table B. What this means is: if B.OPRID is not a unique field or if A.OPRID_ENTERED_BY is not a foreign key for B.OPRID then this answer will not yield the same results as the original query.