我想更改现有查询,但出现以下错误:
不支持的子查询表达式“deleted”:只允许顶级共轭的子查询表达式
现有查询是:
SELECT DISTINCT
*
FROM
geoposition_import AS geo
-- do not take into account data for deleted users
WHERE
EXISTS (
SELECT 1
FROM geoposition_import_users AS u
WHERE u.id = geo.userId
AND NOT u.deleted
);
在我们改变之后 userId
在 geoposition_import
可以为空,因为地理位置现在也可以由计算机创建。所以我把查询改为
SELECT DISTINCT
*
FROM
geoposition_import AS geo
-- do not take into account data for deleted users
WHERE
geo.userId IS NULL -- data from non users (e.g. machines) is still fine
OR
EXISTS (
SELECT 1
FROM geoposition_import_users AS u
WHERE u.id = geo.userId
AND NOT u.deleted
);
得到了上面提到的错误。
我在谷歌上搜索发现了限制条件:https://docs.cloudera.com/hdpdocuments/hdp3/hdp-3.1.5/using-hiveql/content/hive_hive_subquery_limitations.html
所以我的猜测是:手术室才是问题所在。
现在我的问题是:
为什么错误消息指出“delete”是问题所在?
如何重写查询以使其工作?
我想到的唯一解决办法是:将条件分解成不同的视图,然后执行 UNION ALL
.
比如:
CREATE VIEW IF NOT EXISTS geoposition_import_from_non_users AS
SELECT DISTINCT
*
FROM
geoposition_import AS geo
WHERE
geo.userId IS NULL;
CREATE VIEW IF NOT EXISTS geoposition_import_from_users AS
SELECT DISTINCT
*
FROM
geoposition_import AS geo
-- do not take into account data for deleted users
WHERE
EXISTS (
SELECT 1
FROM geoposition_import_users AS u
WHERE u.id = geo.userId
AND NOT u.deleted
);
-- staged data with possible duplicates removed
CREATE VIEW IF NOT EXISTS geoposition_import_distinct AS
SELECT * FROM geoposition_import_from_non_users
UNION ALL
SELECT * FROM geoposition_import_from_users;
有什么意见吗?
1条答案
按热度按时间z4bn682m1#
尝试左联接而不是现有联接: