Heuristic Temp Table Transformation - 2

Some time ago I've demonstrated the non-cost based decision for applying the temp table transformation when using CTEs (Common Table/Subquery Expressions). In this note I want to highlight another aspect of this behaviour.Consider the following data creating a table with delibrately wide columns:

create table a
as
  select
          rownum as id
        , rownum as id2
        , rpad('x', 4000) as large_vc1
        , rpad('x', 4000) as large_vc2
        , rpad('x', 4000) as large_vc3
from
          dual
connect by
          level <= 1000
;

exec dbms_stats.gather_table_stats(null, 'a')

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