RTRIM inside LISTAGG?

Question

Good day. I am writing a query that uses LISTAGG and returns results. This is the code I have so far.

   select 
    listagg(rtrim(shop_cde, 1), ', ') within group (order by shop_cde) col1,
    business_cde
    from mytable
    group by business_cde

I expect that this returns results, aggregates them, and trims off 1 character from the right on shop_cde. However, it appears no trimming occurs. Shop_cde still shows in full. Does anyone know how to TRIM inside a LISTAGG function?

Answer 1

The trim() functions are generally used to remove leading and trailing spaces (although you can remove other characters as well).

If you want to discard the last character, use substr() :

select listagg(substr(shop_cde, 1, length(shop_cde) - 1), ', ') within group (order by shop_cde) col1,
       business_cde
from mytable
group by business_cde

Answer 2

Use substr if you want to remove a given number of charcaters from the right, use rtrim if you want an unspecified number of a given character eliminated. Removing on the left would use substr(..., 2) and ltrim , resp.

   select 
    listagg(substr(shop_cde, -1), ', ') within group (order by shop_cde) col1,
    business_cde
    from mytable
    group by business_cde

Answer 3

you should use rtrim(listagg(....) )

select 
rtrim(listagg(shop_cde, ', ') within group (order by shop_cde) ) col1,
business_cde
from mytable
group by business_cde