I have a question regarding the max-statement in a select -
Without the MAX-statemen i have this select:
SELECT stockID, DATE, close, symbol
FROM ta_stockprice JOIN ta_stock ON ta_stock.id = ta_stockprice.stockID
WHERE stockid = 8648
ORDER BY close
At the end i only want to have the max row for the close-column so i tried:
Why i didn´t get date = "2021-07-02" as output?
(i saw that i allways get "2021-07-01" as output - no matter if i use MAX / MIN / AVG...)
The MAX() turns the query into an aggregation query. With no GROUP BY, it returns one row. But the query is syntactically incorrect, because it mixes aggregated and unaggregated columns.
Once upon a time, MySQL allowed such syntax in violation of the SQL Standard but returned values from arbitrary rows for the unaggreged columns.
Use ORDER BY to do what you want:
SELECT stockID, DATE, close, symbol
FROM ta_stockprice JOIN ta_stock ON ta_stock.id = ta_stockprice.stockID
WHERE stockid = 8648
ORDER BY close DESC
LIMIT 1;
Related
I'm trying to get the max of averages by using this query :
select code, avg(note)
from exam
group by code
having avg(note)=(select max(avg(note)) from exam group by code)
but I get this error :
Invalid use of group function
where I had wrong?
Nesting aggregation function at the same level will not work. Altenative approach is to order by avg descending and take first row:
SELECT code, avg(note) AS avg_note
FROM exam
GROUP BY code
ORDER BY avg_note DESC
LIMIT 1;
I am currently still on my SQL educational journey and need some help!
The query I have is as below;
SELECT
Audit_Non_Conformance_Records.kf_ID_Client_Reference_Number,
Audit_Non_Conformance_Records.TimeStamp_Creation,
Audit_Non_Conformance_Records.Clause,
Audit_Non_Conformance_Records.NC_type,
Audit_Non_Conformance_Records.NC_Rect_Received,
Audit_Non_Conformance_Records.Audit_Num
FROM Audit_Non_Conformance_Records
I am trying to tweak this to show only the most recent results based on Audit_Non_Conformance_Records.TimeStamp_Creation
I have tried using MAX() but all this does is shows the latest date for all records.
basically the results of the above give me this;
But I only need the result with the date 02/10/2019 as this is the latest result. There may be multiple results however. So for example if 02/10/2019 had never happened I would need all of the idividual recirds from the 14/10/2019 ones.
Does that make any sense at all?
You can filter with a subquery:
SELECT
kf_ID_Client_Reference_Number,
TimeStamp_Creation,
Clause,
NC_type,
NC_Rect_Received,
Audit_Num
FROM Audit_Non_Conformance_Records a
where TimeStamp_Creation = (
select max(TimeStamp_Creation)
from Audit_Non_Conformance_Records
)
This will give you all whose TimeStamp_Creation is equal to the greater value available in the table.
If you want all records that have the greatest day (exluding time), then you can do:
SELECT
kf_ID_Client_Reference_Number,
TimeStamp_Creation,
Clause,
NC_type,
NC_Rect_Received,
Audit_Num
FROM Audit_Non_Conformance_Records a
where cast(TimeStamp_Creation as date) = (
select cast(max(TimeStamp_Creation) as date)
from Audit_Non_Conformance_Records
)
Edit
If you want the latest record per refNumber, then you can correlate the subquery, like so:
SELECT
kf_ID_Client_Reference_Number,
TimeStamp_Creation,
Clause,
NC_type,
NC_Rect_Received,
Audit_Num
FROM Audit_Non_Conformance_Records a
where TimeStamp_Creation = (
select max(TimeStamp_Creation)
from Audit_Non_Conformance_Records a1
where a1.refNumber = a.refNumber
)
For performance, you want an index on (refNumber, TimeStamp_Creation).
If you want the latest date in SQL Server, you can express this as:
SELECT TOP (1) WITH TIES ancr.kf_ID_Client_Reference_Number,
ancr.TimeStamp_Creation,
ancr.Clause,
ancr.NC_type,
ancr.NC_Rect_Received,
ancr.Audit_Num
FROM Audit_Non_Conformance_Records ancr
ORDER BY CONVERT(date, ancr.TimeStamp_Creation) DESC;
SQL Server is pretty good about handling dates with conversions, so I would not be surprised if this used an index on TimeStamp_Creation.
I have a database function that I am able to get the correct results from, but when I try to use SUM to total the results it returns a much higher value.
SELECT
SUM([DATABASE].[dbo].[fn_GetCharges]([TABLE1_DATE],[TABLE1_CUST],[TABLE1_SITE],[TABLE1_SERV])) AS [GROSS_REVENUE]
FROM [DATABASE].[dbo].[TABLE1]
WHERE
[TABLE1_ROUT] = '1234'
AND [TABLE1_DATE] = '2018-05-08'
This returns a SUM value of about 15,740.
If I remove the SUM and GROUP BY the function then it shows each of the returned values, which I manually totalled to about 750.
I'm using Microsoft SQL Server 2014.
We don't know what is in your function, but you could probably output your raw data first and then sum it next.
;WITH cte AS (
SELECT
[DATABASE].[dbo].[fn_GetCharges]([TABLE1_DATE],[TABLE1_CUST],[TABLE1_SITE],[TABLE1_SERV]) AS [GROSS_REVENUE]
FROM [DATABASE].[dbo].[TABLE1]
WHERE
[TABLE1_ROUT] = '1234'
AND [TABLE1_DATE] = '2018-05-08'
GROUP BY whatever_you_grouped_by_that_gave_correct_results
)
SELECT SUM(gross_revenue) AS gross_revenue
FROM cte
Wondering if you used group by clause in the query since I don't see one posted.
Group By (columns) Having (condition). What you specified in the 'where' goes in the 'Having' clause
Suppose I want to retrieve the swimmer and their time at the 75th Percentile for each day.
This is what I was trying to do:
SELECT tableA.DATE, tableA.SWIMMER, tableA.TIME
OVER (PARTITION BY tableA.DATE)
FROM tableA
WHERE RANK = CEIL(0.75 * NUM_OF_SWIMMERS);
But this errors at the OVER statement.
What's the best way to get the data I need?
Thanks!
Your error is that the OVER clause of a windowing function requires an ORDER BY clause.
But assuming that num_swimmers , why not just return
select
date,
swimmer,
time
from tablea
where
RANK = CEIL(0.75 * NUM_OF_SWIMMERS)
?
The WHERE clause will ensure the only rows returned are the 75th percentile for a given day
I'm struggling to get the correct result with this query:
select max(kts.my_date), kts.name
join ktt on ktt.someId = kts.someOtherId
where ktt.someId = 'example'
group by kts.name;
I have two (possibly stupid) questions:
Will this max() take time into account? I know that order by does if the dates are the same. Does max do the same?
This is connected to my previous question, but when I run the query above, if the dates are same, it orders it by the name. I want the latest date at the top. Do I need to put an order by clause for the date in? If so, using Max is pointless, right?
Thanks for the help.
Yes,
--2
select max(kts.my_date) over (partition by kts.name) as maxdate, kts.name
from -- chose your table
join ktt on ktt.someId = kts.someOtherId
where ktt.someId = 'example'
order by --chose here your column
give this a try