How can I get the same result using single query?

Question

There are 3 tables
1) tool_desc -
a master table for storing tool records,
columns tool_no, tool_chg,
# of records = 1.5 Millon
2) step_desc -
a master table for storing plan wise step records,
columns plan_id, step_key,
# of records = 3700 Million
3) step_tool - a transaction table storing tools to the steps,
columns plan_id, step_key, tool_no, tool_chg
For each step in the step_desc table, I need to randomly fetch 1 to 50 tools from tool_desc and insert them into step_tool table.
Using PL/SQL block, it is like the following -
begin
for x in (select plan_id, step_key from step_desc) loop
insert into step_tool(
plan_id,
step_key,
tool_no,
tool_chg)
select
plan_id,
x.step_key,
tool_no,
tool_chg
from
tool sample(0.1)
where
rownum <= trunc(dbms_random.value(1,51))
commit;
end loop;
end;
I need to do the same using a single query so that I can use the CTAS (create table as select) statement and load the data as a bulk.
Can I do that?

Answer 1

If they have parent child releation, you can use connect by prior clause,