Add support for arbitrary subqueries in WHERE/HAVING, including inside disjuncts

select 
  c_customer_sk,
  c_first_name,
  c_last_name
from customer
where
 (exists (select *
          from web_sales, date_dim
          where c_customer_sk = ws_bill_customer_sk and
                ws_sold_date_sk = d_date_sk and
                d_date = '2002-01-01') 
  or 
  exists (select * 
          from catalog_sales, date_dim
          where c_customer_sk = cs_ship_customer_sk and
                cs_sold_date_sk = d_date_sk and
                d_date = '2002-01-01') 
)
order by 1;

with 
v1 as (
  select 
     ws_bill_customer_sk as customer_sk
  from web_sales,
       date_dim
  where ws_sold_date_sk = d_date_sk
  and d_date = '2002-01-01'
  union all
  select 
    cs_ship_customer_sk as customer_sk
  from catalog_sales,
       date_dim 
  where cs_sold_date_sk = d_date_sk
  and d_date = '2002-01-01'
)
select 
  c_customer_sk,
  c_first_name,
  c_last_name
from customer
left semi join v1 on (customer_sk = c_customer_sk)
order by 1