Oracle SQL 分区范围全部而不是范围单一
Posted
技术标签:
【中文标题】Oracle SQL 分区范围全部而不是范围单一【英文标题】:Oracle SQL Partition range all instead of range single 【发布时间】:2020-12-10 13:08:08 【问题描述】:我按日期创建了一个分区表,我在其中划分了 createdate(然后客户创建了一个帐户)。
CREATE TABLE PARTITIONED_customer (
customerId number(10) GENERATED AS IDENTITY,
firstName varchar2(50),
lastName varchar2(50),
email varchar2(50),
createDate date,
active char(1),
PRIMARY KEY (customerId))
PARTITION BY RANGE (createDate)
INTERVAL(NUMTOYMINTERVAL(1, 'MONTH'))
(PARTITION first_quater_2018 VALUES LESS THAN(TO_DATE('01-04-2018','dd-MM-yyyy')),
PARTITION second_quater_2018 VALUES LESS THAN(TO_DATE('01-07-2018','dd-MM-yyyy')),
PARTITION third_quater_2018 VALUES LESS THAN(TO_DATE('01-10-2018','dd-MM-yyyy')),
PARTITION fourth_quater_2018 VALUES LESS THAN(TO_DATE('01-01-2019','dd-MM-yyyy')),
PARTITION first_quater_2019 VALUES LESS THAN(TO_DATE('01-04-2019','dd-MM-yyyy')),
PARTITION second_quater_2019 VALUES LESS THAN(TO_DATE('01-07-2019','dd-MM-yyyy')),
PARTITION third_quater_2019 VALUES LESS THAN(TO_DATE('01-10-2019','dd-MM-yyyy')),
PARTITION fourth_quater_2019 VALUES LESS THAN(TO_DATE('01-01-2020','dd-MM-yyyy')));
这是我想知道客户何时创建帐户的 SQL 查询。我知道查询不完全正确,提前抱歉
select c.createdate, c.firstname, c.lastname, round(sum(p.amount)) as spentmoney
from PARTITIONED_customer c
join PARTITIONED_rental r
on c.customerid = r.customerid
join PARTITIONED_payment_amount p
on p.rentalid = r.rentalid
where c.createdate BETWEEN TO_DATE('01-05-2019','dd-MM-yyyy')
AND TO_DATE('01-06-2019','dd-MM-yyyy')
or (select round(sum(pp.amount)) from PARTITIONED_payment_amount pp
join PARTITIONED_rental rr
on rr.rentalid = pp.rentalid
where rr.customerid=c.customerid) < 50
group by c.firstname, c.lastname,c.createdate
order by c.firstname, c.lastname;
解释器显示所有分区范围,而不是单个。怎么解决?
我用一个简单的查询自己检查了分区,没问题。所以,我认为查询本身有问题。
【问题讨论】:
【参考方案1】:您的查询正在 PARTITIONED_CUSTOMER 上执行 TABLE ACCESS FULL,因此它当然必须搜索所有分区。我建议在分区键上创建索引:
CREATE INDEX PARTITIONED_CUSTOMER_1
ON PARTITIONED_CUSTOMER (CREATEDATE)
LOCAL;
如果您真的愿意,可以在查询中指定 PARTITION 子句:
select c.createdate, c.firstname, c.lastname, round(sum(p.amount)) as spentmoney
from PARTITIONED_customer PARTITION (second_quater_2019) c
INNER join PARTITIONED_rental r
on c.customerid = r.customerid
INNER join PARTITIONED_payment_amount p
on p.rentalid = r.rentalid
where c.createdate BETWEEN TO_DATE('01-05-2019','dd-MM-yyyy') AND
TO_DATE('01-06-2019','dd-MM-yyyy') or
(select round(sum(pp.amount))
from PARTITIONED_payment_amount pp
INNER join PARTITIONED_rental rr
on rr.rentalid = pp.rentalid
where rr.customerid=c.customerid) < 50
group by c.firstname, c.lastname,c.createdate
order by c.firstname, c.lastname
另外 - 您在此查询中有 AND
和 OR
条件,它们没有被完全括起来。 AND
和 OR
的评估顺序可能不是你想象的那样。你是说
(c.createdate BETWEEN TO_DATE('01-05-2019','dd-MM-yyyy') AND
TO_DATE('01-06-2019','dd-MM-yyyy')) or
(select round(sum(pp.amount))
from PARTITIONED_payment_amount pp
INNER join PARTITIONED_rental rr
on rr.rentalid = pp.rentalid
where rr.customerid=c.customerid) < 50
或者你的意思是
c.createdate BETWEEN TO_DATE('01-05-2019','dd-MM-yyyy') AND
(TO_DATE('01-06-2019','dd-MM-yyyy') or
(select round(sum(pp.amount))
from PARTITIONED_payment_amount pp
INNER join PARTITIONED_rental rr
on rr.rentalid = pp.rentalid
where rr.customerid=c.customerid) < 50)
如果您像这样混合使用 AND
和 OR
,最好使用括号将操作分组为您想要的,否则您可能无法获得预期的结果。
【讨论】:
以上是关于Oracle SQL 分区范围全部而不是范围单一的主要内容,如果未能解决你的问题,请参考以下文章