EXPLAIN select 100.00 * sum(case when p_type like 'PROMO%' then l_extendedprice * (1 - l_discount) else 0 end) / sum(l_extendedprice * (1 - l_discount)) as promo_revenue from lineitem, part where l_partkey = p_partkey and l_shipdate >= date '1996-07-01' and l_shipdate < date '1996-07-01' + interval '1 month';
        plan         
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         map        
                    
       groupby      
                    
       join         
       indexnl      
                    
 tablescan tablescan
 lineitem  part     
(9 rows)