Sql 删除一列中具有特定值且同一行或连续行的另一列中缺少值的行
我的数据集由不同公司的每日时间序列组成,我使用PostgreSQL。 我的数据集中有一个指示符变量,取值为1,-1,大部分时间为0。如果指标变量不为0,且某公司在该日(指标日)或第二天的另一列中缺少值,则该公司应完全从数据集中排除 我们可以考虑以下示例数据:Sql 删除一列中具有特定值且同一行或连续行的另一列中缺少值的行,sql,postgresql,gaps-and-islands,Sql,Postgresql,Gaps And Islands,我的数据集由不同公司的每日时间序列组成,我使用PostgreSQL。 我的数据集中有一个指示符变量,取值为1,-1,大部分时间为0。如果指标变量不为0,且某公司在该日(指标日)或第二天的另一列中缺少值,则该公司应完全从数据集中排除 我们可以考虑以下示例数据: date company indicator value 2012-01-02 A 0 2 2012-01-02 B 0
date company indicator value
2012-01-02 A 0 2
2012-01-02 B 0 9
2012-01-02 C 0 1
2012-01-02 D 0 3
2012-01-03 A 1 NULL
2012-01-03 B 0 NULL
2012-01-03 C -1 1
2012-01-03 D 0 2
2012-01-04 A 0 1
2012-01-04 B 0 1
2012-01-04 C 0 NULL
2012-01-04 D 1 4
2012-01-05 A 0 4
2012-01-05 B 0 2
2012-01-05 C 0 1
2012-01-05 D 0 7
因此,A必须被排除在外,因为它在指标日缺少一个值,而C是因为它在指标日的第二天缺少一个值
我尝试了以下方法:
CREATE TABLE to_delete
AS SELECT * FROM mytable
WHERE company IN(
SELECT company
FROM mytable
WHERE date BETWEEN (SELECT date FROM mytable WHERE indicator != 0)
AND (SELECT date+1 FROM mytable WHERE indicator != 0)
AND indicator != 0)
AND date BETWEEN (SELECT date FROM mytable WHERE indicator != 0)
AND (SELECT date+1 FROM mytable WHERE indicator != 0)
DELETE FROM mytable WHERE company in (SELECT DISTINCT company FROM to_delete);
如果示例数据集中只存在一个不等于零的指示符值,则该方法有效。对于多行,PostgreSQL返回一个错误,表示我的子查询返回了多行
我真的在努力解决这个问题。您是否知道一种解决方案,或者可能是实现所需结果的完全其他方法 我会用一个 仅删除有问题的行
Ervin的变体看起来更清晰,如果这是少量的数据,并且子选择的数量无关紧要。
SELECT * FROM tbl t
-- DELETE FROM tbl t
WHERE indicator <> 0
AND EXISTS (
SELECT 1
FROM tbl t1
WHERE day IN (t.day, t.day + 1)
AND t1.company = t.company
AND t1.value IS NULL
)
DELETE FROM tbl t
USING (
SELECT DISTINCT company
FROM tbl t
WHERE indicator <> 0
AND EXISTS (
SELECT 1
FROM tbl t1
WHERE day IN (t.day, t.day + 1)
AND t1.company = t.company
AND t1.value IS NULL
)
) del
WHERE t.company = del.company
DELETE FROM test WHERE company IN (
WITH
for_check AS (SELECT date, company FROM test WHERE indicator != 0)
SELECT test.company
FROM test
INNER JOIN for_check fc
ON test.date IN (fc.date, fc.date + 1)
AND fc.company = test.company
WHERE test.value IS NULL
)