I have this query:
SELECT
EnrollmentID, MarketID
FROM
Contracts AS CO
LEFT JOIN
Customers AS C ON C.EnrollmentID = CO.BatchID AND MarketID = 'AB'
WHERE
C.EnrollmentID IS NULL
Here, I have a question that in this query is it possible that the query will verify data for MarketID = 'AB' in left join because as per WHERE condition?
I am getting result of EnrollmentIDs and MarketIDs are all NULL.
Note: The LEFT JOIN keyword returns all the rows from the left table (Contracts ), even if there are no matches in the right table (Customers ).
Now, if you want to select right table column and there are no matching data in the right table ,like.
SELECT CO.EnrollmentID, CO.MarketID ,C.Some_col
FROM Contracts AS CO
LEFT JOIN Customers AS C ON C.EnrollmentID = CO.BatchID
so, C.Some_col column will get all the null value for no matching rows in the right table.i think this is the reason why you are getting the null value for
MarketIDs and EnrollmentIDs.
hope, this help you.
Related
I have 4 tables, the 1st table 'LD0P0K' is the main table i need to join with 2nd 'LD0P0K01' and 3rd 'LD0P0K04' with the 1st column value 'HUSHLNR' and get the 'PNR' from both tables and then join with last table 'LD0P0A' to get the values with 'PNR'.
I tried the below solution but its not giving the data from 3rd table and giving 6 records with 2 rows for each 2nd table.
Select HS.HUSHLNR, HS.FOMDAT,HS.TOMDAT,HSM.PNR,HSM.FAMHUVUD,HSM.MARK,HSM.AVFOMDAT,HSM.AVTOMDAT,P.KUNDNUMMER,P.FODDAT from LD0P0K HS
LEFT OUTER JOIN LD0P0K01 HSM on HS.HUSHLNR = HSM.HUSHLNR
LEFT OUTER JOIN LD0P0K04 CHM on HS.HUSHLNR = CHM.HUSHLNR
LEFT OUTER JOIN LD0P0A P on p.PNR= HSM.PNR AND p.PNR = CHM.PNR
Where HS.HUSHLNR='906'
You can simply use Union to combined the fields
Here is the link for Union to understand
SQL Union
and here is the code change it whatever you want
Select HS.HUSHLNR as HUSHLNR, HS.fromdate as FromDte,HSM.PNR as PNR from LD0P0K HS
inner JOIN LD0P0K01 HSM on HS.HUSHLNR = HSM.HUSHLNR
union
Select CHM.HUSHLNR as HUSHLNR, '' as FromDte,CHM.PNR as PNR from LD0P0K04 CHM
order by PNR
Output:
I guess the problem comes down to this: what are some extreme scenarios where using a LEFT OUTER JOIN DOES NOT return the values as expected? Because in the result set I'm expecting the fields I joined on (item and ID) + any NULL values where the rows don't match, but item and ID don't show up.
Info:
qry_HersheySAPMaxDate2 returns 95 rows.
qry_HersheySAPMaxDate2 could have NULL values for MaxOfMaxOfjob_Date, SumOfSumOfqty_on_hand, product_code, and whse, whereas ID and item will always have a value.
qry_HersheySAPMaxDate3 returns 85 rows.
qry_HersheySAPMaxDate3 does not have any NULL values in any field, but excludes 10 id and item rows.
The query:
SELECT
qry_HersheySAPMaxDate3.ID,
qry_HersheySAPMaxDate3.item,
qry_HersheySAPMaxDate3.MaxOfMaxOfjob_date, qry_HersheySAPMaxDate3.SumOfSumOfqty_on_hand, qry_HersheySAPMaxDate3.product_code,
qry_HersheySAPMaxDate3.whse,
qry_HersheySAPMaxDate3.jobnumber
FROM
qry_HersheySAPMaxDate2
LEFT JOIN qry_HersheySAPMaxDate3 ON (qry_HersheySAPMaxDate2.item = qry_HersheySAPMaxDate3.item) AND (qry_HersheySAPMaxDate2.ID = qry_HersheySAPMaxDate3.ID);
Result set using my query + the suggestion in one of the answers to use LEFT OUTER JOIN instead:
Screenshot
You complain about your query producing entirely blank rows. Let's see why:
You outer join qry3 to qry2. That means when there is no match for a qry2 record in qry3, then a pseudo qry3 record with all columns set to null gets joined.
In your query you select only fields from qry3, so in an outer join case they are all null. Select qry2.ID and qry2.item instead of qry3.ID and qry3.item to see the values that have no match:
SELECT
qry_HersheySAPMaxDate2.ID,
qry_HersheySAPMaxDate2.item,
You should use LEFT OUTER JOIN if you want the NULL values to be included in the result
I'm trying to find rows where a value in table 1 column A are not in table 2 column A
This is the query...
SELECT contactsid
FROM contacts
WHERE (email1 NOT IN (SELECT email
FROM old_contact))
It returns 0 rows, which I know is incorrect. There are many rows in contacts.email1 that are not in old_contact.email
How should I be writing this query?
My guess is that old_contract.email takes on a NULL value.
For this reason, not exists is often a better choice:
SELECT contactsid
FROM contacts c
WHERE NOT EXISTS (SELECT 1
FROM old_contract oc
WHERE c.email = oc.email1
) ;
You could also add where email1 is not null to the subquery. However, I find just using not exists is generally safer in case I forget that condition.
Try:
SELECT contactsid
FROM Contacts a
LEFT JOIN old_contact b
ON a.email1 = b.email
WHERE b.email IS NULL
This will join Contacts to old_contact using a LEFT JOIN -- a type of join that, based on the join condition, returns all records from the left side (i.e. Contacts) even if no records exist on the right side. Then, the WHERE clause filters the results so that it returns only the records from the left side where the ride side records don't exist.
I have problems joining 2 table let say I have a column on the 1st table name nationalitycode(this is number) and it fetches the description(it could be american, chinese etc) depending on the first table nationalitycode. So I tried inner join the table so the first inner join is good and working perfectly.
here is the code:
SELECT person.firstnm, person.middlenm, person.lastnm, refcd.description
FROM person
INNER JOIN refcd
ON person.natcd = refcd.id;
However when I try to join the 2nd column from the 1st table let say the column name is gencd(gendercode its a foreign key) but when I updated the query to inner join 2 column from one table getting the value from one column in the 2nd table I get this error.
"Column ambigously defined" I get this error and I understand this my question is is there anyway to achieve my desired output? I want to join 2 table, specifically joining 2 column on table 1 to 1 column in table 2.
Here is my updated query:
SELECT person.firstnm, person.middlenm, person.lastnm, refcd.description
FROM person
INNER JOIN refcd
ON person.natcd = refcd.id
INNER JOIN refcd
ON person.gencd = refcd.id;
Help is really appreciated.
Your query should be
SELECT person.firstnm, person.middlenm, person.lastnm, refcd.description
FROM person INNER JOIN refcd ON person.natcd = refcd.id
INNER JOIN refcd R2 ON person.gencd = R2.id;
I have the following tables
Payment
PayTypeId, Description
0 , Credit
1, Debit
2,Master
ActualPayment
Id,PayTypeId,Amount
1,1,10
Here is the output i am looking at
Id,PayTypeId,Amount
1,0,NULL
1,1,10
1,2,NULL
Basically I want all the records of ActualPayment including all payment types.
Here is the query i have used but am not getting any records
select
*
from #ActualPayments ap
left join #Payment p on ap.paytypeid = p.paytypeid
where p.paytypeid is null
If you want one record for each of the three PayTypeID values, then you need those three records on the left-hand side of the LEFT JOIN.
Equally, if you want the ActuallPaymentID on each output line, that value needs to be on the left hand side.
It's all leading you down the wrong avenue with the data that you have, and the tables that you have described.
With just those two tables in your question, I would use this layout instead...
SELECT
ap.ActualPaymentID,
p.PayTypeID,
SUM(CASE WHEN ap.PayTypeID = p.PayTypeID THEN ap.Amount END) AS Amount
FROM
ActualPayments AS ap
CROSS JOIN
Payment AS p
GROUP BY
ap.ActualPaymentID,
p.PayTypeID
You aren't receiving any records because you are filtering everything out with the WHERE clause p.paytypeid is null
Try running it without the WHERE clause.
Edit: The below SQL should return the correct information. I've used a CROSS JOIN to create an in-line view. This should remove the unwanted NULLs.
SELECT t1.id, t1.paytypeid, t2.amount
FROM (
SELECT id, payment.paytypeid
FROM #ActualPayments
CROSS JOIN #Payment
) t1
LEFT OUTER JOIN #ActualPayments t2
ON t1.paytypeid = t2.paytypeid
;
I think you want a FULL OUTER JOIN:
select
*
from #ActualPayments ap
full outer join #Payment p
on ap.paytypeid = p.paytypeid
;
This will return all rows from the ActualPayments table along with their corresponding values from Payment - if there is any. Additional it will return all rows from Payment for which no ActualPayments exist.
Please note: The where clause of your sample query must not be used!
I'm confused why you would want to do this, but here's one way
select ap.Id, pt.PayTypeId, ap2.Amount
from #ActualPayments ap
cross join #PaymentTypes pt
left join #ActualPayments ap2
on pt.PayTypeId = ap2.PayTypeId
and ap.Id = ap2.id