我有简单的表员工ID，开始年份，结束年份。我必须找到有多少员工在最短的一年到最高年份工作。如果分钟是2000年和最大year sysdate它应列出2000年至2017年所有那些年份的工作人员数
答案 0 :(得分：0)
我结合了一些问题，我现在想的就是我不会，请检查这是否是无问题的解决方案：
with YEARS as
(
select (to_char(SAP_VALID_FROM,'YYYY') + level -1) AS YEARS
from
(
SELECT MIN(SAP_VALIDFROM) AS SAP_VALID_FROM, MAX(SYSDATE) AS SAP_VALID_TO
FROM MA_MITARBEITER_TH
) YEARS
connect by level < = to_char(SYSDATE,'YYYY') - to_char(SAP_VALID_FROM,'YYYY')+1
),
YEARS_SCOPE AS
(
SELECT PERSONALNUMMER, EXTRACT(YEAR FROM (MIN(SAP_VALIDFROM))) AS ARBEIT_BEGINN,
CASE WHEN EXTRACT(YEAR FROM (MAX(SAP_VALIDTO)))='9999' THEN EXTRACT(YEAR FROM (MAX(SYSDATE))) ELSE EXTRACT(YEAR FROM (MAX(SAP_VALIDTO))) END AS ARBEIT_SCHLUSS
FROM MA_MITARBEITER_TH
WHERE TIMEGROUP='AKT'
GROUP BY PERSONALNUMMER
)
select COUNT(*), YEARS
FROM YEARS,YEARS_SCOPE
WHERE YEARS BETWEEN ARBEIT_BEGINN AND ARBEIT_SCHLUSS
GROUP BY YEARS
ORDER BY YEARS;