i'm just learning SQL today and i never thought how fun it's until i'm fiddling with it.
I got a problem and i need a help.
i have 2 tables, Customer and Rate, with details stated below
Customer
idcustomer = int
namecustomer = varchar
rate = decimal(3,0)
with value as described:
idcustomer---namecustomer---rate
1---JOHN DOE---100
2---MARY JANE---90
3---CLIVE BAKER---12
4---DANIEL REYES---47
Rate
rate = decimal(3,0)
description = varchar(40)
with value as described:
rate---description
10---G Rank
20---F Rank
30---E Rank
40---D Rank
50---C Rank
60---B Rank
70---A Rank
80---S Rank
90---SS Rank
100---SSS Rank
Then i ran query below in order to round all values in customer.rate field then inner join it with rate table.
SELECT *, round(rate,-1) as roundedrate
FROM customer INNER JOIN rate ON customer.roundedrate = rate.rate
It didn't produce this result:
idcustomer---namecustomer---rate---roundedrate---description
1---JOHN DOE---100---100---SSS Rank
2---MARY JANE---90---90---SS Rank
3---CLIVE BAKER---12---10---G Rank
4---DANIEL REYES---47---50---C Rank
Is there anything wrong with my code ?
Your query should produce an 'ambigious column' error because you're not specifying a table name when referring to rate (in round(rate,-1)), which exists in both tables.
Also, the where part of a sql query is executed before the select part, so you can't refer to the alias customer.roundedrate in your where statement.
Try this instead
SELECT *, round(customer.rate,-1) as roundedrate
FROM customer INNER JOIN rate ON round(customer.rate,-1) = rate.rate
http://sqlfiddle.com/#!9/e94a60/2
I would suggest a correlated subquery for this:
select c.*,
(select r.description
from rate r
where r.rate <= c.rate
order by r.rate desc
fetch first 1 row only
) as description
from customer c;
Note: fetch first 1 row only is ANSI standard SQL, which some databases do not support. MySQL uses limit. Older versions of SQL Server use select top 1 instead.
Related
I have the following query that return me: 100 rows
SELECT uni_id, uni_mast_id, uni_type
FROM UNIVERSITIES
WHERE uni_master ='SO88'AND uni_stat= 'OK'
now i need to do a join with another table and to obtain last entry of that day then:
SELECT uni_id, uni_teach_name, MAX(cal_update), cal_status
FROM UNIVERSITIES
LEFT JOIN CALENDAR
ON unı_id = cal_id
WHERE uni_master = 'SO88'
AND uni_stat = 'OK'
AND cal_name = 'REGISTRED'
GROUP BY uni_id, uni_teach_name, uni_stat
ORDER BY cal_update
but this query gives me 102 records, because cal_update appears 2 times.
One for example with date : 22-OCT-2020 11:34:55 another for the same uni_id at time 22-OCT-2020 11:30:22
I want just to get the max date for that date, not both.
In this case the query with the join needs to return the same records of the first select query.
I think you can do what you want using row_number():
SELECT UNI_ID, UNI_TEACH_NAME, CAL_UPDATE, CAL_STATUS
FROM (SELECT U.UNI_ID, U.UNI_TEACH_NAME, C.CAL_UPDATE, C.CAL_STATUS,
ROW_NUMBER() OVER (PARTITION BY U.UNI_ID, TRUNC(C.CAL_UPDATE) ORDER BY C.CAL_UPDATE DESC) as seqnum
FROM UNIVERSITIES U LEFT JOIN
CALENDAR C
ON U.UNI_ID = C.CAL_ID AND C.CAL_NAME = 'REGISTRED'
WHERE U.UNI_MASTER = 'SO88' AND
U.UNI_STAT= 'OK'
) UC
WHERE seqnum = 1;
I have to guess where the columns come from, because the question is not clear. Any filtering columns from CALENDAR should be in the ON clause if you are using a LEFT JOIN.
You can replace the last part of the query, while aliasing the MAX(cal_update) with cal_update , as
ORDER BY cal_update DESC
FETCH FIRST 1 ROW WITH TIES
for DB version 12c+ to descendingly order by the concerned column in order to pick the record with the latest value for that column.
WITH TIES option stand for bringing all records with the same datetime values, might be replaced with ONLY in order to bring only one row even for those cases occur.
The column call_status(within the select list) should be removed which's a non- aggregated column
As an alternative to a subquery and rank, you could use KEEP...LAST :
SELECT U.UNI_ID,
U.UNI_TEACH_NAME,
MAX(C.CAL_UPDATE) AS CAL_UPDATE,
MAX(C.CAL_STATUS) KEEP (DENSE_RANK LAST ORDER BY C.CAL_UPDATE) AS CAL_STATUS
FROM UNIVERSITIES U
LEFT JOIN CALENDAR C
ON U.UNI_ID = C.CAL_ID
AND C.CAL_NAME = 'REGISTRED'
WHERE U.UNI_MASTER = 'SO88'
AND U.UNI_STAT= 'OK'
GROUP BY U.UNI_ID,
U.UNI_TEACH_NAME,
TRUNC(C.CAL_UPDATE)
I've moved the CAL_NAME check into the outer join's ON clause; if it's in the WHERE clause then it will effectively turn it back into an inner join. So this will get one row per university per day that the calendar was updated: "I want just to get the max date for that date". And it will show nulls for the calendar fields if there is no matching calendar, since it's an outer join.
If you actually only want the latest update on any day then just remove the TRUNC(C.CAL_UPDATE) from the grouping:
SELECT U.UNI_ID,
U.UNI_TEACH_NAME,
MAX(C.CAL_UPDATE) AS CAL_UPDATE,
MAX(C.CAL_STATUS) KEEP (DENSE_RANK LAST ORDER BY C.CAL_UPDATE) AS CAL_STATUS
FROM UNIVERSITIES U
LEFT JOIN CALENDAR C
ON U.UNI_ID = C.CAL_ID
AND C.CAL_NAME = 'REGISTRED'
WHERE U.UNI_MASTER = 'SO88'
AND U.UNI_STAT= 'OK'
GROUP BY U.UNI_ID,
U.UNI_TEACH_NAME
db<>fiddle with some made-up data; and also (just for fun) showing Gordon's query with the calendar name clause in both places to show the difference, and to show this gets the same result for that dummy data. (And an 18c version which shows Barbaros' too; getting back a single row.)
I need to update the following query so that it only returns one child record (remittance) per parent (claim).
Table Remit_To_Activate contains exactly one date/timestamp per claim, which is what I wanted.
But when I join the full Remittance table to it, since some claims have multiple remittances with the same date/timestamps, the outermost query returns more than 1 row per claim for those claim IDs.
SELECT * FROM REMITTANCE
WHERE BILLED_AMOUNT>0 AND ACTIVE=0
AND REMITTANCE_UUID IN (
SELECT REMITTANCE_UUID FROM Claims_Group2 G2
INNER JOIN Remit_To_Activate t ON (
(t.ClaimID = G2.CLAIM_ID) AND
(t.DATE_OF_LATEST_REGULAR_REMIT = G2.CREATE_DATETIME)
)
where ACTIVE=0 and BILLED_AMOUNT>0
)
I believe the problem would be resolved if I included REMITTANCE_UUID as a column in Remit_To_Activate. That's the REAL issue. This is how I created the Remit_To_Activate table (trying to get the most recent remittance for a claim):
SELECT MAX(create_datetime) as DATE_OF_LATEST_REMIT,
MAX(claim_id) AS ClaimID,
INTO Latest_Remit_To_Activate
FROM Claims_Group2
WHERE BILLED_AMOUNT>0
GROUP BY Claim_ID
ORDER BY Claim_ID
Claims_Group2 contains these fields:
REMITTANCE_UUID,
CLAIM_ID,
BILLED_AMOUNT,
CREATE_DATETIME
Here are the 2 rows that are currently giving me the problem--they're both remitts for the SAME CLAIM, with the SAME TIMESTAMP. I only want one of them in the Remits_To_Activate table, so only ONE remittance will be "activated" per Claim:
enter image description here
You can change your query like this:
SELECT
p.*, latest_remit.DATE_OF_LATEST_REMIT
FROM
Remittance AS p inner join
(SELECT MAX(create_datetime) as DATE_OF_LATEST_REMIT,
claim_id,
FROM Claims_Group2
WHERE BILLED_AMOUNT>0
GROUP BY Claim_ID
ORDER BY Claim_ID) as latest_remit
on latest_remit.claim_id = p.claim_id;
This will give you only one row. Untested (so please run and make changes).
Without having more information on the structure of your database -- especially the structure of Claims_Group2 and REMITTANCE, and the relationship between them, it's not really possible to advise you on how to introduce a remittance UUID into DATE_OF_LATEST_REMIT.
Since you are using SQL Server, however, it is possible to use a window function to introduce a synthetic means to choose among remittances having the same timestamp. For example, it looks like you could approach the problem something like this:
select *
from (
select
r.*,
row_number() over (partition by cg2.claim_id order by cg2.create_datetime desc) as rn
from
remittance r
join claims_group2 cg2
on r.remittance_uuid = cg2.remittance_uuid
where
r.active = 0
and r.billed_amount > 0
and cg2.active = 0
and cg2.billed_amount > 0
) t
where t.rn = 1
Note that that that does not depend on your DATE_OF_LATEST_REMIT table at all, it having been subsumed into the inline view. Note also that this will introduce one extra column into your results, though you could avoid that by enumerating the columns of table remittance in the outer select clause.
It also seems odd to be filtering on two sets of active and billed_amount columns, but that appears to follow from what you were doing in your original queries. In that vein, I urge you to check the results carefully, as lifting the filter conditions on cg2 columns up to the level of the join to remittance yields a result that may return rows that the original query did not (but never more than one per claim_id).
A co-worker offered me this elegant demonstration of a solution. I'd never used "over" or "partition" before. Works great! Thank you John and Gaurasvsa for your input.
if OBJECT_ID('tempdb..#t') is not null
drop table #t
select *, ROW_NUMBER() over (partition by CLAIM_ID order by CLAIM_ID) as ROW_NUM
into #t
from
(
select '2018-08-15 13:07:50.933' as CREATE_DATE, 1 as CLAIM_ID, NEWID() as
REMIT_UUID
union select '2018-08-15 13:07:50.933', 1, NEWID()
union select '2017-12-31 10:00:00.000', 2, NEWID()
) x
select *
from #t
order by CLAIM_ID, ROW_NUM
select CREATE_DATE, MAX(CLAIM_ID), MAX(REMIT_UUID)
from #t
where ROW_NUM = 1
group by CREATE_DATE
I am still new to SQL and getting my head around the whole sub-query aggregation to display some results and was looking for some advice:
The tables might look something like:
Customer: (custID, name, address)
Account: (accountID, reward_balance)
Shop: (shopID, name, address)
Relational tables:
Holds (custID*, accountID*)
With (accountID*, shopID*)
How can I find the store that has the least reward_balance?
(The customer info is not required at this point)
I tried:
SELECT accountID AS ACCOUNT_ID, shopID AS SHOP_ID, MIN(reward_balance) AS LOWEST_BALANCE
FROM Account, Shop, With
WHERE With.accountID = Account.accountID
AND With.shopID=Shop.shopID
GROUP BY
Account.accountID,
Shop.shopID
ORDER BY MIN(reward_balance);
This works in a way that is not intended:
ACCOUNT_ID | SHOP_ID | LOWEST_BALANCE
1 | 1 | 10
2 | 2 | 40
3 | 3 | 100
4 | 4 | 1000
5 | 4 | 5000
As you can see Shop_ID 4 actually has a balance of 6000 (1000+5000) as there are two customers registered with it. I think I need to SUM the lowest balance of the shops based on their balance and display it from low-high.
I have been trying to aggregate the data prior to display but this is where I come unstuck:
SELECT shopID AS SHOP_ID, MIN(reward_balance) AS LOWEST_BALANCE
FROM (SELECT accountID, shopID, SUM(reward_balance)
FROM Account, Shop, With
WHERE
With.accountID = Account.accountID
AND With.shopID=Shop.shopID
GROUP BY
Account.accountID,
Shop.shopID;
When I run something like this statement I get an invalid identifier error.
Error at Command Line : 1 Column : 24
Error report -
SQL Error: ORA-00904: "REWARD_BALANCE": invalid identifier
00904. 00000 - "%s: invalid identifier"
So I figured I might have my joining condition incorrect and the aggregate sorting incorrect, and would really appreciate any general advice.
Thanks for the lengthy read!
Approach this problem one step at time.
We're going to assume (and we should probably check this) that by least reward_balance, that refers to the total of all reward_balance associated with a shop. And we're not just looking for the shop that has the lowest individual reward balance.
First, get all of the individual "reward_balance" for each shop. Looks like the query would need to involve three tables...
SELECT s.shop_id
, a.reward_balance
FROM `shop` s
LEFT
JOIN `with` w
ON w.shop_id = s.shop_id
LEFT
JOIN `account` a
ON a.account_id = w.account_id
That will get us the detail rows, every shop along with the individual reward_balance amounts associated with the shop, if there are any. (We're using outer joins for this query, because we don't see any guarantee that a shops is going to be related to at least one account. Even if it's true for this use case, that's not always true in the more general case.)
Once we have the individual amounts, the next step is to total them for each shop. We can do that using a GROUP BY clause and a SUM() aggregate.
SELECT s.shop_id
, SUM(a.reward_balance) AS tot_reward_balance
FROM `shop` s
LEFT
JOIN `with` w
ON w.shop_id = s.shop_id
LEFT
JOIN `account` a
ON a.account_id = w.account_id
GROUP BY s.shop_id
At this point, with MySQL we could add an ORDER BY clause to arrange the rows in ascending order of tot_reward_balance, and add a LIMIT 1 clause if we only want to return a single row. We can also handle the case when tot_reward_balance is NULL, assigning a zero in place of the NULL.
SELECT s.shop_id
, IFNULL(SUM(a.reward_balance),0) AS tot_reward_balance
FROM `shop` s
LEFT
JOIN `with` w
ON w.shop_id = s.shop_id
LEFT
JOIN `account` a
ON a.account_id = w.account_id
GROUP BY s.shop_id
ORDER BY tot_reward_amount ASC, s.shop_id ASC
LIMIT 1
If there are two (or more) shops with the same least value of tot_reward_amount, this query returns only one of those shops.
Oracle doesn't have the LIMIT clause like MySQL, but we can get equivalent result using analytic function (which is not available in MySQL). We also replace the MySQL IFNULL() function with the Oracle equivalent NVL() function...
SELECT v.shop_id
, v.tot_reward_balance
, ROW_NUMBER() OVER (ORDER BY v.tot_reward_balance ASC, v.shop_id ASC) AS rn
FROM (
SELECT s.shop_id
, NVL(SUM(a.reward_balance),0) AS tot_reward_balance
FROM shop s
LEFT
JOIN with w
ON w.shop_id = s.shop_id
LEFT
JOIN account a
ON a.account_id = w.account_id
GROUP BY s.shop_id
) v
HAVING rn = 1
Like the MySQL query, this returns at most one row, even when two or more shops have the same "least" total of reward_balance.
If we want to return all of the shops that have the lowest tot_reward_balance, we need to take a slightly different approach.
The best approach to building queries is step wise refinement; in this case, start by getting all of the individual reward_amount for each shop. Next step is to aggregate the individual reward_amount into a total. The next steps is to pickout the row(s) with the lowest total reward_amount.
In SQL Server, You can try using a CTE:
;with cte_minvalue as
(
select rank() over (order by Sum_Balance) as RowRank,
ShopId,
Sum_Balance
from (SELECT Shop.shopID, SUM(reward_balance) AS Sum_Balance
FROM
With
JOIN Shop ON With.ShopId = Shop.ShopId
JOIN Account ON With.AccountId = Account.AccountId
GROUP BY
Shop.shopID)ShopSum
)
select ShopId, Sum_Balance from cte_minvalue where RowRank = 1
I have 2 SQL Tables
unit_transaction
unit_detail_transactions
(tables schema here: http://sqlfiddle.com/#!3/e3204/2 )
What I need is to perform an SQL Query in order to generate a table with balances. Right now I have this SQL Query but it's not working fine because when I have 2 transactions with the same date then the balance is not calculated correctly.
SELECT
ft.transactionid,
ft.date,
ft.reference,
ft.transactiontype,
CASE ftd.isdebit WHEN 1 THEN MAX(ftd.debitaccountid) ELSE MAX(ftd.creditaccountid) END as financialaccountname,
CAST(COUNT(0) as tinyint) as totaldetailrecords,
ftd.isdebit,
SUM(ftd.amount) as amount,
balance.amount as balance
FROM unit_transaction_details ftd
JOIN unit_transactions ft ON ft.transactionid = ftd.transactionid
JOIN
(
SELECT DISTINCT
a.transactionid,
SUM(CASE b.isdebit WHEN 1 THEN b.amount ELSE -ABS(b.amount) END) as amount
--SUM(b.debit-b.credit) as amount
FROM unit_transaction_details a
JOIN unit_transactions ft ON ft.transactionid = a.transactionid
CROSS JOIN unit_transaction_details b
JOIN unit_transactions ft2 ON ft2.transactionid = b.transactionid
WHERE (ft2.date <= ft.date)
AND ft.unitid = 1
AND ft2.unitid = 1
AND a.masterentity = 'CONDO-A'
GROUP BY a.transactionid,a.amount
) balance ON balance.transactionid = ft.transactionid
WHERE
ft.unitid = 1
AND ftd.isactive = 1
GROUP BY
ft.transactionid,
ft.date,
ft.reference,
ft.transactiontype,
ftd.isdebit,
balance.amount
ORDER BY ft.date DESC
The result of the query is this:
Any clue on how to perform a correct SQL that will show me the right balances ordered by transaction date in descendant mode?
Thanks a lot.
EDIT: THINK OF 2 POSSIBLE SOLUTIONS
The problem is generated when you have the same date in 2 transactions, so here is what Im going to do:
Save Date and Time into "date" column. That way there won't be 2 exact dates.
OR
Create a "priority" column and set the priority for each record. So if I found that the date already exists and it has priority = 1 then the current priority will be 2.
What do you think?
There are two ways to do a running sum. I am going to show the syntax on a simpler table, to give you an idea.
Some databases (Oracle, PostgreSQL, SQL Server 2012, Teradata, DB2 for instance) support cumulative sums directly. For this you use the following function:
select sum(<val>) over (partition by <column> order by <ordering column>)
from t
This is a windows function that will calculate the running sum of for each group of records identified by . The order of the sum is .
Alas, many databases don't support this functionality, so you would need to do a self join to do this in a single SELECT query in the database:
select t.column, sum(tprev.<val>) as cumsum
from t left join
t tprev
where t.<column> = tprev.<column> and
t.<ordering column> >= tprev.<ordering column>
group by t.column
There is also the possibility of creating another table and using a cursor to assign the cumulative sum, or of doing the sum at the application level.
i have a trivia game and i want to reward users for 2 events:
1) answering correctly
2) sending a question to the questions pool
i want to query for score and rank of a specific player and i use this query:
SELECT (correct*10+sent*30) AS score, #rank:=#rank+1 AS rank
FROM ( trivia_players
JOIN ( SELECT COUNT(*) AS sent, senderid
FROM trivia_questions
WHERE senderid='$userid'
) a
ON trivia_players.userid=a.senderid
)
ORDER BY score DESC
and it works if the player is in both tables i.e answered correctly AND sent a question.
but it doesn't work if a player hasn't sent a question
any idea how to fix this query? ($userid is the given parameter)
thanks!
Thanks Tom! only problem is the ranks are not correct:
userid score rank
58217 380 1
12354 80 3
32324 0 2
I would probably do it like this:
SELECT
user_id,
score,
rank
FROM
(
SELECT
TP.user_id,
(TP.correct * 10) + (COUNT(TQ.sender_id) * 30) AS score,
#rank:=#rank + 1 AS rank
FROM
Trivia_Players TP
LEFT OUTER JOIN Trivia_Questions TQ ON
TQ.sender_id = TP.user_id
GROUP BY
TP.user_id,
TP.correct
ORDER BY
score DESC
) AS SQ
WHERE
SQ.user_id = $user_id
I don't use MySQL much, so the syntax may not be perfect. I think that you can use a subquery like this in MySQL. Assuming that MySQL handles COUNT() by only counting rows with a non-null value for , this should work.
The keys are that you do a COUNT over a non-null column from Trivia Questions so that it counts them up by the user and you need to use a subquery so that you can get ranks for everyone BEFORE constraining to a particular user id.
Have you tried using a RIGHT JOIN or LEFT JOIN? Just off the top of my head!