Equivalent to PostgreSQL array() / array_to_string() functions in Oracle 9i

Question

I\'m hoping to return a single row with a comma separated list of values from a query that returns multiple rows in Oracle, essentially flattening the returned rows into a s

Answer 1

In 10g I definitely prefer the COLLECT option mentioned at the end of Tim's article.

The nice thing about that approach is that the same underlying function (that accepts the collection as an argument), can be used both as an aggregate and as a multiset function:

SELECT deptno, tab_to_string(CAST(MULTISET(SELECT ename FROM emp 
WHERE deptno = dept.deptno) AS t_varchar2_tab), ',') FROM dept

However in 9i that's not available. SYS_CONNECT_BY_PATH is nice because it's flexible, but it can be slow, so be careful of that.