SQL Multiple Conditions in max statement not working - sql

I am attempting to filter my table and get the item that sold for the most amount of money. In order to do this I am using "AuctionOpen" to determine whether or not the auction is still open. The auction cannot be open and have the item been sold (later I will use this for the most expensive item available).
I am able to use the AND operator to compare AuctionOpen by using the following:
select s.*
from auctionsite.dbo.Auction s
where s.HighestBid = (select max(s2.HighestBid) from auctionsite.dbo.Auction
s2) and s.AuctionOpen = 0;
When I set this equal to zero I get results, but when I set it equal to 1, it only returns the column titles even though there are values set to 1 in the table.
Results when compared to 0:
Results when compared to 1:

Clearly, the highest bid is on a record where AuctionOpen <> 1.
I recommend using order by and fetch (or the equivalent in your database):
select s.*
from auctionsite.dbo.Auction s
where s.AuctionOpen = 0
order by s.HIghestBid desc
fetch first 1 row only
In SQL Server, use either select top (1) or offset 0 rows fetch first 1 row only.

I think you should try the Count aggregate function
here, try this:
**Select count(Item_name) As
[Item with the highest money]
from table_name
Group by Item_name DSEC;**
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Related

SQL: getting rows where some 'x' column value is a maximal one [duplicate]

This question already has answers here:
How can I SELECT rows with MAX(Column value), PARTITION by another column in MYSQL?
(22 answers)
Closed 11 months ago.
I am trying to get data from my database.
Query upon sub-query upon another sub-query - and as the intermediate result I get looks like this:
item
quantity
pen
34
pencil
42
notebook
42
eraser
12
I need to build another query upon this result set to get the rows where item_quantity has it's maximal value (42 in the example above). The rows with pencils and notebooks. However, I have found out that the task is a bit trickier than I expected it to be.
SELECT * FROM sub_query_result HAVING quantity = MAX(quantity)
always returns an empty result set
SELECT * FROM sub_query_result HAVING quantity = 42
is pointless since I need to know the exact max quantity in advance
SELECT * FROM sub_query_result WHERE quantity = MAX(quantity)
simply works not ("Invalid use of group function")
I can see solutions that work but that I do not like -- due to extra actions I need to take on my back-end code that executes this sql request, or due to their inefficiency:
I can create a temporary table, get max. quantity from it and place to a variable. Then I can use this variable inside the query to that temporary table and get the data I need.
I can do
SELECT * FROM query_result HAVING quantity = (SELECT MAX(quantity) FROM
<Query upon sub-query upon another sub-query that shall return query_result>)
but that way I request the very same data twice! which in general is not a good approach.
So... Anything I missed? Any simple and elegant solutions that can solve my problem?
Order by quantity descending to get the max values first. Only select the first row, i.e. the one having the max values. ANSI SQL version:
SELECT * FROM query_result
ORDER BY quantity DESC
FETCH FIRST 1 ROW WITH TIES
WITH TIES means you can get several rows, if there are several rows having the same maximum quantity.

Sql get the latest row in a table by date - double select vs order by

Have a query that uses double select (with select max) to fetch the row with the latest 'calculation_time' column among multiple rows which can have the same 'patient_set_id'. If there are multiple rows with the same 'patient_set_id', only the row with the latest 'calculation_time' should be retrieved. Calculation time is a date.
So far I've tried this but I'm not really sure if there is any better way for this, maybe using ORDER BY. But I'm very new to sql and need to know which one would be the fastest and more appropriate?
SELECT median from diagnostic_risk_stats WHERE
calculation_time=(SELECT MAX(calculation_time) FROM diagnostic_risk_stats WHERE
patient_set_id = UNHEX(REPLACE('5a9dbfca-74d6-471a-af27-31beb4b53bb2', "-","")));
You can use not exists as follows:
SELECT median
from diagnostic_risk_stats t
WHERE not exists
(Select 1 from diagnostic_risk_stats tt
Where t.patient_set_id = tt.patient_set_id
And tt.calculation_time > t.calculation_time)
And t.patient_set_id = UNHEX(REPLACE('5a9dbfca-74d6-471a-af27-31beb4b53bb2', "-",""));

How to get 0 if no row found from sql query in sql server

I am getting blank value with this query from sql server
SELECT TOP 1 Amount from PaymentDetails WHERE Id = '5678'
it has no row,that is why its returning blank,So I want if no row then it should return 0
I already tried with COALESCE ,but its not working
how to solve this?
You are selecting an arbitrary amount, so one method is aggregation:
SELECT COALESCE(MAX(Amount), 0)
FROM PaymentDetails
WHERE Id = '5678';
Note that if id is a number, then don't use single quotes for the comparison.
To be honest, I would expect SUM() to be more useful than an arbitrary value:
SELECT COALESCE(SUM(Amount), 0)
FROM PaymentDetails
WHERE Id = '5678';
You can wrap the subquery in an ISNULL:
SELECT ISNULL((SELECT TOP 1 Amount from PaymentDetails WHERE Id = '5678' ORDER BY ????),0) AS Amount;
Don't forget to add a column (or columns) to your ORDER BY as otherwise you will get inconsistent results when more than one row has the same value for Id. If Id is unique, however, then remove both the TOP and ORDER BY as they aren't needed.
You should never, however, use TOP without an ORDER BY unless you are "happy" with inconsistent results.

Oracle Data Gaps

im looking for a query to fill this condition:
That currently gives us the number of BACs at the entity (which is something we need). The database assigns the BAC IDs consecutively within each accounting entity. So we need to add one more field to the query showing the current highest BAC ID at the entity. And once we have that, just filter the results down to anyplace the number of records doesn't equal the highest ID.
My current query:
select accounting_entity_id, count(bac_id)
from dc.pl_bac_information
group by accounting_entity_id
having count(bac_id) > 1;
Use analytic functions for this:
select bi.*
from (select bi.*, max(bac_id) over (partition by accounting_entity_id) as max_bac_id
from dc.pl_bac_information bi
) bi
where bac_id = max_bac_id;
This assumes you are using Oracle.
SELECT ACCOUNTING_ENTITY_ID
FROM DC.PL_BAC_INFORMATION
HAVING COUNT(BAC_ID) > 1 AND COUNT(BAC_ID) != MAX(BAC_ID)
GROUP BY ACCOUNTING_ENTITY_ID;

Check Sequence in Max Min Values

I have a database table that Stores Maximum and Minimum Price Breaks for a Product.
Does anyone know of the SQL which say if I have a break from one Max to the Min of the next item. E.g. 1-10 12-20 I would like it to return me either the numbers that are missing or at the very least a count or bool if it can detect a break from the Absolute Min and the Absolute Max by going through each range.
SQL Server (MSSQL) 2008
For a database that supports window functions, like Oracle:
SELECT t.*
, CASE LAG(maxq+1, 1, minq) OVER (PARTITION BY prod ORDER BY minq)
WHEN minq
THEN 0
ELSE 1
END AS is_gap
FROM tbl t
;
This will produce is_gap = 1 for a row that forms a gap with the previous row (ordered by minq). If your quantity ranges can overlap, the required logic would need to be provided.
http://sqlfiddle.com/#!4/f609e/4
Something like this, giving max quantities that aren't the overall max for the product and don't have a min quantity following them:
select prev.tbProduct_Id,prev.MaxQuantity
from yourtable prev
left join (select tbProduct_ID, max(MaxQuantity) MaxQuantity from yourtable group by tbProduct_id) maxes
on maxes.tbProduct_ID=prev.tbProduct_Id and maxes.MaxQuantity=prev.MaxQuantity
left join yourtable next
on next.tbProduct_Id=prev.tbProduct_Id and next.MinQuantity=prev.MaxQuantity+1
where maxes.tbProduct_Id is null and next.tbProduct_Id is null;
This would fail on your sample data, though, because it would expect a row with MinQuantity 21, not 20.