Oracle equivalent to SQL Server STUFF function?

Question

Hi,

Does Oracle have its own implementation of SQL Server stuff function?

Stuff allows you to receive one value from a multi row select. Consider my situation below

 ID   HOUSE_REF   PERSON
 1      A         Dave
 2      A         John
 3      B         Bob

I would like to write a select statement, but I want the PERSON names to be in a single row.

For example, when I select from this table, I want to achieve the following

HOUSE_REF   PERSONS
A           Dave, John
B           Bob

I haven't been able to find a simple solution so far, it may be a case of writing my own function to use, but I'm not entirely sure of how to approach this, any ideas?

The main business use of this, will be to have a select statement that shows each house, and against that house to have one column which lists everyone that lives in that house. The house ref in this select must be unique, hence needing to concatenate the persons

Thanks

Answer 1

You can write a custom aggregate function to do this. This string you generate is limited to 4k characters.

http://www.sqlsnippets.com/en/topic-11591.html

There is an undocumented, unsupported function WMSYS.WM_CONCAT to do the same thing.

http://www.psoug.org/reference/undocumented.html

Answer 2

Oracle 11.2 includes a new function LISTAGG to do this.

Prior to that you could use Tom Kyte's STRAGG function.

Answer 3

The "no add-ons/no undocumented functions" Oracle solution (prior to 11.2 as Tony mentions) is:

select c1, ltrim(sys_connect_by_path(c2,','),',') persons
 from
  (
   select c1, c2, 
    row_number() over (partition by c1 order by c2 ) rn
     from
      (
       select house_ref c1, person c2 
        from housetable 
      )
   )
  where connect_by_isleaf=1
  connect by prior rn+1 =rn and prior c1 = c1
  start with rn=1
;