How to select rows where multiple joined table values meet selection criteria?
Given the following sample table 开发者_开发百科schema
Customer Table
CustID
1
2
3
Invoice Table
CustID InvoiceID
1 10
1 20
1 30
2 10
2 20
3 10
3 30
The objective is to select all customers who have an InvoiceID value of 10 and 20 (not OR). So, in this example customers w/ CustID=1 and 2 would be returned.
How would you construct the SELECT statement?
Use:
SELECT c.custid
FROM CUSTOMER c
JOIN INVOICE i ON i.custid = c.custid
WHERE i.invoiceid IN (10, 20)
GROUP BY c.custid
HAVING COUNT(DISTINCT i.invoiceid) = 2
The key thing is that the counting of i.invoiceid
needs to equal the number of arguments in the IN
clause.
The use of COUNT(DISTINCT i.invoiceid)
is in case there isn't a unique constraint on the combination of custid and invoiceid -- if there's no chance of duplicates you can omit the DISTINCT from the query:
SELECT c.custid
FROM CUSTOMER c
JOIN INVOICE i ON i.custid = c.custid
WHERE i.invoiceid IN (10, 20)
GROUP BY c.custid
HAVING COUNT(i.invoiceid) = 2
The Group By answers will work unless it is possible for there to be multiples of CustID/InvoiceId in the Invoice table. Then you might get some unexpected results. I like the answer below a little better because it mirrors more closely the logic as you are describing it.
Select CustID
From Customer
Where
Exists (Select 1 from Invoice Where CustID=Customer.CustID and InvoiceID=10)
and
Exists (Select 1 from Invoice Where CustID=Customer.CustID and InvoiceID=20)
select CustID
from InvoiceTable
where InvoiceID in (10,20)
group by CustID
having COUNT(distinct InvoiceID) = 2
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