Dynamic pivot in oracle sql

Question

... pivot (sum(A) for B in (X))

Now B is of datatype varchar2 and X is a string of varchar2 values separated by commas.
Values for X are select distinct values

Answer 1

You can't put a non constant string in the IN clause of the pivot clause.
You can use Pivot XML for that.

From documentation:

subquery A subquery is used only in conjunction with the XML keyword. When you specify a subquery, all values found by the subquery are used for pivoting

It should look like this:

select xmlserialize(content t.B_XML) from t_aa
pivot xml(
sum(A) for B in(any)
) t;

You can also have a subquery instead of the ANY keyword:

select xmlserialize(content t.B_XML) from t_aa
pivot xml(
sum(A) for B in (select cl from t_bb)
) t;

Here is a sqlfiddle demo