Oracle SQL 分区范围全部而不是范围单一答案

【问题标题】：Oracle SQL Partition range all instead of range singleOracle SQL 分区范围全部而不是范围单一
【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】：

标签： sql oracle query-optimization database-partitioning

【解决方案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】：