Remove duplicate help

Question

I have a Table with no dups on customer_id (as primary key) and some that have a single dup, meaning 2 rows maximum, here is an example of the data:
I want to flatten the dups rows to one row based on this rule:
customer_id      EMAIL_1                        EMAIL_2
12345            [email protected]      N/A
12345                  N/A                      [email protected] want it to be:
12345 [email protected] [email protected]
removing the N/A
all the duplicates are like that and in no other way, I am not sure how to do this, I tried a mix of len and max() but that did not work.
Thanks!

Answer 1

Hi,
Kodiak_Seattle wrote:
I have a Table with no dups on customer_id (as primary key) and some that have a single dup, meaning 2 rows maximum, here is an example of the data:I'm confused. If cusotmer_id is the primary key, then you can't possibly have two rows with the same customer_id.
If customer_id is a vARCHAR2, then you might have two rows whose customer_ids are hard to tell apart, e.g. '12345' (5 characters) and '12345 ' (6 characters, including a space at the end).
Whenever you have a problem, please post CREATE TABLE (including PRIMARY KEY constraint) and INSERT statements for a little sample data, and the results you want from that data.
Always say which version of Oracle you're using.
I want to flatten the dups rows to one row based on this rule:
customer_id      EMAIL_1                        EMAIL_2
12345            [email protected]      N/A
12345                  N/A                      [email protected] want it to be:
12345 [email protected] [email protected]
removing the N/A
all the duplicates are like that and in no other way, I am not sure how to do this, I tried a mix of len and max() but that did not work.Assuming customer_id is not the primary key after all, and you want to ignore the string 'N/A' in either email_1 or email_2, you might do something like this:
SELECT       customer_id
,       MIN (NULLIF (email_1, 'N/A'))     AS email_1
,       MIN (NULLIF (email_2, 'N/A'))     AS email_2
FROM       table_x
GROUP BY  customer_id
;Edited by: Frank Kulash on Jan 6, 2012 4:27 PM