我有以下选择:
SELECT
COALESCE (opened.ano, closed.ano) AS ano,
COALESCE (opened.mes, closed.mes) AS mes,
COALESCE (opened.cnt, 0) AS opened_cases,
COALESCE (closed.cnt, 0) AS closed_cases
FROM
(
SELECT
YEAR (OPEN_DATE) AS ano,
MONTH (OPEN_DATE) AS mes,
COUNT (*) AS cnt
FROM
TABLE1,
TABLE2
WHERE
TABLE1.USERNAME = TABLE2.USERNAME
AND TABLE2.GROUP = 'SUPPORT'
GROUP BY
YEAR (OPEN_DATE),
MONTH (OPEN_DATE)
) opened
FULL OUTER JOIN (
SELECT
YEAR (CLOSE_DATE) AS ano,
MONTH (CLOSE_DATE) AS mes,
COUNT (*) AS cnt
FROM
TABLE1,
TABLE2
WHERE
TABLE1.USERNAME = TABLE2.USERNAME
AND TABLE2.GROUP = 'SUPPORT'
GROUP BY
YEAR (CLOSE_DATE),
MONTH (CLOSE_DATE)
) closed ON opened.ano = closed.ano
AND opened.mes = closed.mes
ORDER BY
COALESCE (opened.ano, closed.ano) ASC,
COALESCE (opened.mes, closed.mes) ASC;
结果是:
情况:
具有空值的第一行丢失,因为选择中没有空条件。
谢谢
最佳答案
select
coalesce(opened.ano, closed.ano) as ano,
coalesce(opened.mes, closed.mes) as mes,
coalesce(opened.cnt, 0) as opened_cases,
coalesce(closed.cnt, 0) as closed_cases
from
(
select
year(open_time) as ano,
month(open_time) as mes,
count(*) as cnt
from table1
where groupdesc = 'SUPPORT'
group by year(open_time), month(open_time)
) opened
full outer join
(
select
year(close_time) as ano,
month(close_time) as mes,
count(*) as cnt
from table1
where groupdesc = 'SUPPORT'
group by year(close_time), month(close_time)
) closed
on opened.ano = closed.ano and opened.mes = closed.mes
where closed.mes is not null
order by coalesce(opened.ano, closed.ano) desc, coalesce(opened.mes, closed.mes) desc;
这是添加了 WHERE 子句的 SQL。 您的评论似乎表明您要查找的内容包含在此结果集中。 有 10 个 Opened_cases 和 8 个 closed_cases。
关于使用 Null 值选择和计数,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/23272260/