How NOT to restrict no of rows from two tables

Question

I have two identical tables Invoice and Payment. The only difference is Invoice_id,Invoice_Amt and Payment_id,Payment_Amt columns that shows different ids and amounts. The bank_ids, names, account_types are same. Invoice table has 3 rows and Payment has 2. Simply meaning that there were 3 invoices generated but the bank received 2 payments. I want to show Invoice_Amt and Payment_Amt using sql query. But its giving me total 6 rows. Whereas, I want 3 from Invoice and 2 rows from Payment table to show side-by-side.
CREATE TABLE invoice
( invoice_id NUMBER
bank_id NUMBER,
bank_name VARCHAR2(256),
invoice_amount NUMBER);
----Invoice table has 3 rows showing 3 Invoice Amts
CREATE TABLE payment
( payment_id NUMBER
bank_id NUMBER,
bank_name VARCHAR2(256),
payment_amount NUMBER);
----Payment table has 2 rows showing 2 Payments
After executing this sql statement below, I get 6 rows:
select inv.invoice_amount,pymt.payment_amount from invoice inv,payment pymt where inv.bank_id=pymt.bank_id;
How can I show 3 rows for Invoice and 2 for Payment..?
Thank you.

Answer 1

Hi,
So you want
the 1st invoice to appear side-by-side with the 1st payment,
the 2nd invoice to appear side-by-side with the 2nd payment,
the nth invoice to appear side-by-side with the nth payment.
But, if there are an uneqaul numner of payments and invoices, all the payments and all the invoices must still be shown, alone on a row if necessary.
That sounds like a job for FULL OUTER JOIN.
Use the analytic ROW_NUMBER fucntion to determine which is the 1st, 2nd, ..., nth row in each table, for each bank.
WITH     invoice_plus_r_num     AS
     SELECT     bank_id, bank_name
     ,      invoice_amount
     ,     ROW_NUMBER () OVER ( PARTITION BY  bank_id, bank_name
                               ORDER BY          invoice_id
                       )         AS r_num
     FROM    invoice
,     payment_plus_r_num     AS
     SELECT     bank_id, bank_name
     ,      payment_amount
     ,     ROW_NUMBER () OVER ( PARTITION BY  bank_id, bank_name
                               ORDER BY          payment_id
                       )         AS r_num
     FROM    payment
SELECT       NVL (i.bank_id,   p.bank_id)          AS bank_id
,       NVL (i.bank_name, p.bank_name)     AS bank_name
,       i.invoice_amount
,       p.payment_amount
FROM          invoice_plus_r_num     i
FULL OUTER JOIN     payment_plus_r_num     p  ON   i.bank_id     = p.bank_id
                                    AND     i.bank_name     = p.bank_name
                            AND     i.r_num          = p.r_num
ORDER BY  bank_id     -- you can use column aliases here
,       bank_name
,       NVL (i.r_num, p.r_num)
;You mentioned something about accounts, but didn't include that in the CREATE TABLE statements. You'll probably want to add that wherever I used bank_id and bank_name, above.
Are invoce and payment actually views, rather than tables? If not, you should have a separate bank table, and only include the bank_id in the other tables.
I hope this answers your question.
If not, post a little sample data (CREATE TABLE and INSERT statements, relevant columns only) for all tables, and also post the results you want from that data.
Explain, using specific examples, how you get those results from that data.
Always say which version of Oracle you're using.
Edited by: Frank Kulash on Feb 3, 2011 12:32 PM