我想获取在给定日期(基于id_external)添加和删除的记录,所以我使用了下面的查询,这给了我预期的结果,但它耗费了大量的时间和LOGICALREAD太高了,...有人可以简化吗
SELECT ar.*
FROM t_row_data ar
WHERE ar.id_instance IS NULL
AND ar.id_category IS NULL
AND ar.source_name ='SomeSource'
AND ar.eco_date IN (date '2017-12-22', date '2017-12-21')
AND ar.active = 'Y'
AND ar.id_external IN
(SELECT ar.id_external
FROM t_row_data ar
WHERE ar.id_instance IS NULL
AND ar.id_category IS NULL
AND ar.source_name ='SomeSource'
AND ar.eco_date IN (date '2017-12-22', date '2017-12-21')
AND ar.active = 'Y'
GROUP BY ar.id_external
HAVING COUNT(1) = 1)
答案 0 :(得分:1)
假设表t_row_data
包含列id_external, id_instance, id_category, source_name, eco_date, active, col7, col8, ...
,您可以像这样重写查询:
select id_external, null as id_instance, null as id_category,
'SomeSource' as source_name, max(eco_date) as eco_date, 'Y' as active,
max(col7) as col7, max(col8) as col8, ...
from t_row_data
where id_instance is null
and id_category is null
and source_name = 'SomeSource'
and eco_date between date '2017-12-21' and date '2017-12-22'
and active = 'Y'
group by id_external
having count(*) = 1
;