Question

Cannot get this statement to update the table and am almost certain my problem is in concatenation syntax.

Please take a look and tell me if you see what I am going wrong here..

Thank you !!

UPDATE TAB1 s  
        SET s.user_NUM =   
             (select e.USER# 
                  from TAB2 e   
                  where ('e.LAST_NAME'||','||' E.FIRST_NAME')= s.DEALER);

Answer 1

I think those are supposed to be columns in TAB2? If so, you need to drop the quote marks:

UPDATE TAB1 s
        SET s.user_NUM =   
             (select e.USER# 
                  from TAB2 e   
                  where (e.LAST_NAME||', '||E.FIRST_NAME)= s.DEALER);

Otherwise you’re looking to match records in TAB1 where DEALER = 'e.LAST_NAME, E.FIRST_NAME' (i.e. a literal), which I don’t think is what you meant at all.

---

“When I put a space behind the comma, I got an error that a single row
query returns more than one row.”

So, more than one row in TAB2 matches a row in TAB1. This now becomes an investigation into your data.

If there is only one occurrence of e.USER# for e.LAST_NAME||', '||E.FIRST_NAME you’re fine: you can just add DISTINCT into the sub-query. Check that with:

select e.LAST_NAME||', '||E.FIRST_NAME
       , count(distinct e.USER#) 
from TAB2 e   
group by e.LAST_NAME||', '||E.FIRST_NAME
      having count(distinct e.USER#) > 1

If that query returns any rows you’re going to need to decide how to handle multiple hits.

Likewise, you need to decide what action to take if there is no row in TAB2 which matches a row in TAB1. At the moment that’s going to set s.user_NUM to NULL. Maybe that’s what you want.

These are decisions about business rules: only you know what you want to do.