使用位图连接索引优化OLAP查询

1. select s.prod_id,s.promo_id,s.channel_id
2. from sales_A s, products_A pd, promotions_A pm, channels_A ch
   where s.prod_id = pd.prod_id
     and s.promo_id = pm.promo_id
     and s.channel_id = ch.channel_id
     and pd.prod_id = 27;

1. alter table products_A add constraint products_pk primary key(prod_id);

1. create bitmap index sales_A_bjix
2. on sales_A
   ( pr.prod_id, pm.promo_id, ch.channel_id )
   from sales_A a, products_A pr, promotions_A pm, channels_A ch
   where a.prod_id = pr.prod_id
     and a.promo_id = pm.promo_id
     and a.channel_id = ch.channel_id
   tablespace sh
   nologging;

1. column index_name format a15
2. column inner_table format a15
   column inner_col format a15
   column outer_table format a15
   column outer_col format a15
   select index_name, inner_table_name inner_table, inner_table_column inner_col,
     outer_table_name outer_table, outer_table_column outer_col
   from user_join_ind_columns
   where index_name = 'SALES_A_BJIX';

INDEX_NAME      INNER_TABLE     INNER_COL       OUTER_TABLE     OUTER_COL
--------------- --------------- --------------- --------------- ---------------
SALES_A_BJIX    SALES_A         PROD_ID         PRODUCTS_A      PROD_ID
SALES_A_BJIX    SALES_A         PROMO_ID        PROMOTIONS_A    PROMO_ID
SALES_A_BJIX    SALES_A         CHANNEL_ID      CHANNELS_A      CHANNEL_ID