是否可以根据同一GBQ表中的其他日期选择分区日期范围?
_partitiondate的数据类型为时间戳
purchase_date的数据类型为字符串
以下是我正在尝试做的事情-
_PARTITIONDATE < DATE(CAST(purchase_date as TIMESTAMP))
and _PARTITIONDATE >= date_add(date(CAST(purchase_date as TIMESTAMP)), interval -30 day)
我得到以下错误-
Cannot query over table 'project.dataset.table' without a filter over column(s) '_PARTITION_LOAD_TIME', '_PARTITIONDATE', '_PARTITIONTIME' that can be used for partition elimination
有文献表明这是可能的(有关更多详细信息,请参阅使用伪列查询分区(,下面是文献中建议的结构:
_PARTITIONDATE >= "2018-01-29" AND _PARTITIONDATE < "2018-01-30"
或
_PARTITIONDATE BETWEEN '2016-01-01' AND '2016-01-02'
问题是,正如您正确建议的那样,比较值应该是TIMESTAMP数据类型,因此可以采用不同的方法:
_PARTITIONDATE < TIMESTAMP(purchase_date)
and _PARTITIONDATE >= TIMESTAMP_ADD(TIMESTAMP(purchase_date), interval -30 day)
我认为以下内容应该有效:
SELECT
columns
FROM
dataset.table
WHERE
_PARTITIONDATE BETWEEN TIMESTAMP_SUB(TIMESTAMP(purchase_date), interval 30 day)
AND TIMESTAMP(purchase_date)