关于位图连接索引
Jordan 说:
SELECT /*+index(ss_maintain_record testbit1, bitinfo) */
COUNT
FROM ss_maintain_record,CS_CUSTOMER,cs_purchase_info
WHERE CS_CUSTOMER.Row_Id= ss_maintain_record.customer_id
AND cs_purchase_info.row_id = ss_maintain_record.customer_car_id
Jordan 说:
在这条语句中，我建了两个位图连接索引
Jordan 说:
ss_maintain_record testbit1,
Jordan 说:
ss_maintain_record bitinfo,
Jordan 说:
脚本如下
Jordan 说:
CREATE BITMAP INDEX testbit1
ON ss_maintain_record(CS_CUSTOMER.Row_Id)
FROM CS_CUSTOMER,ss_maintain_record
WHERE CS_CUSTOMER.Row_Id=ss_maintain_record.customer_id ;
Jordan 说:
CREATE BITMAP INDEX bitinfo
ON ss_maintain_record(cs_purchase_info.Row_Id)
FROM cs_purchase_info,ss_maintain_record
WHERE cs_purchase_info.Row_Id=ss_maintain_record.customer_car_id ;
Jordan 说:
SELECT
/*+index(ss_maintain_record testbit1) */
COUNT
FROM ss_maintain_record,CS_CUSTOMER--cs_purchase_info
WHERE CS_CUSTOMER.Row_Id= ss_maintain_record.customer_id
Jordan 说:
这样查效率很高
Jordan 说:
SELECT
/*+index(ss_maintain_record bitinfo) */
COUNT
FROM ss_maintain_record,cs_purchase_info
-- WHERE CS_CUSTOMER.Row_Id= ss_maintain_record.customer_id
WHERE cs_purchase_info.row_id = ss_maintain_record.customer_car_id
Jordan 说:
这样查效率很高
Jordan 说:
现在我想把这三个表做个表连接，如何做？
Jordan 说:
SELECT /*+index(ss_maintain_record testbit1) +index(ss_maintain_record bitinfo) */
COUNT
FROM ss_maintain_record,CS_CUSTOMER,cs_purchase_info
WHERE CS_CUSTOMER.Row_Id= ss_maintain_record.customer_id
AND cs_purchase_info.row_id = ss_maintain_record.customer_car_id
Jordan 说:
我这样做了一下，效率低
问题点数：0、回复次数：0Top
